Delete pyop (#21094)

### Description
Remove the "--enable_language_interop_ops" build flag, because the code
is incompatible with the latest numpy, and the build flag is not used
anywhere except a macOS CI pipeline. It does not seem to have a ship
plan.


### Motivation and Context
The build error was:
```
onnxruntime/core/language_interop_ops/pyop/pyop.cc:122:85: error: no member named 'elsize' in '_PyArray_Descr'
                                  static_cast<int64_t>(PyArray_DescrFromType(type)->elsize),
                                                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~  ^
```

cmake/CMakeLists.txt

@@ -123,7 +123,6 @@ option(onnxruntime_GCOV_COVERAGE "Compile with options necessary to run code cov
 option(onnxruntime_DONT_VECTORIZE "Do not vectorize operations in Eigen" OFF)
 
 option(onnxruntime_USE_FULL_PROTOBUF "Link to libprotobuf instead of libprotobuf-lite when this option is ON" OFF)
-option(onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS "Enable operator implemented in language other than cpp" OFF)
 option(onnxruntime_DEBUG_NODE_INPUTS_OUTPUTS "Dump debug information about node inputs and outputs when executing the model." OFF)
 cmake_dependent_option(onnxruntime_DEBUG_NODE_INPUTS_OUTPUTS_ENABLE_DUMP_TO_SQLDB "Build dump debug information about node inputs and outputs with support for sql database." OFF "onnxruntime_DEBUG_NODE_INPUTS_OUTPUTS" OFF)
 option(onnxruntime_USE_DML "Build with DirectML support" OFF)
@@ -439,13 +438,6 @@ if (onnxruntime_ENABLE_MEMORY_PROFILE)
 endif()
 
 set(ONNX_ML 1)
-if (NOT onnxruntime_ENABLE_PYTHON)
-  set(onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS OFF)
-endif()
-
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  add_compile_definitions(ENABLE_LANGUAGE_INTEROP_OPS)
-endif()
 
 if (NOT (UNIX AND onnxruntime_ENABLE_PYTHON AND onnxruntime_ENABLE_TRAINING AND (NOT onnxruntime_BUILD_SHARED_LIB)))
   if (onnxruntime_ENABLE_TRAINING_TORCH_INTEROP)
@@ -578,7 +570,7 @@ endif()
 #Need python to generate def file
 if (onnxruntime_BUILD_SHARED_LIB OR onnxruntime_ENABLE_PYTHON)
   if (onnxruntime_ENABLE_PYTHON)
-    if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS OR onnxruntime_REQUIRE_PYTHON_EMBED_LIB)
+    if (onnxruntime_REQUIRE_PYTHON_EMBED_LIB)
       find_package(Python 3.8 COMPONENTS Interpreter Development NumPy)
     else()
       find_package(Python 3.8 COMPONENTS Interpreter Development.Module NumPy)

cmake/onnxruntime.cmake

@@ -205,13 +205,6 @@ set(onnxruntime_INTERNAL_LIBRARIES
   onnxruntime_flatbuffers
 )
 
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  list(APPEND onnxruntime_INTERNAL_LIBRARIES
-    onnxruntime_language_interop
-    onnxruntime_pyop
-  )
-endif()
-
 if (onnxruntime_USE_EXTENSIONS)
   list(APPEND onnxruntime_INTERNAL_LIBRARIES
     onnxruntime_extensions

cmake/onnxruntime_python.cmake

@@ -193,10 +193,6 @@ target_link_libraries(onnxruntime_pybind11_state PRIVATE
     ${pybind11_lib}
 )
 
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  target_link_libraries(onnxruntime_pybind11_state PRIVATE onnxruntime_language_interop onnxruntime_pyop)
-endif()
-
 set(onnxruntime_pybind11_state_dependencies
     ${onnxruntime_EXTERNAL_DEPENDENCIES}
     ${pybind11_dep}
@@ -1027,6 +1023,3 @@ if (onnxruntime_USE_QNN)
 endif()
 
 endif()
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  include(onnxruntime_language_interop_ops.cmake)
-endif()

cmake/onnxruntime_training.cmake

@@ -141,10 +141,6 @@ if (onnxruntime_BUILD_UNIT_TESTS)
       Boost::mp11 safeint_interface
   )
 
-  if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-      list(APPEND ONNXRUNTIME_LIBS onnxruntime_language_interop onnxruntime_pyop)
-  endif()
-
   if(UNIX AND NOT APPLE)
     if (HAS_NO_MAYBE_UNINITIALIZED)
       target_compile_options(onnxruntime_training_mnist PUBLIC "-Wno-maybe-uninitialized")

cmake/onnxruntime_unittests.cmake

@@ -583,10 +583,6 @@ if(onnxruntime_USE_ARMNN)
   list(APPEND onnxruntime_test_providers_dependencies onnxruntime_providers_armnn)
 endif()
 
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  set(ONNXRUNTIME_INTEROP_TEST_LIBS PRIVATE onnxruntime_language_interop onnxruntime_pyop)
-endif()
-
 set(ONNXRUNTIME_TEST_LIBS
     onnxruntime_session
     ${ONNXRUNTIME_INTEROP_TEST_LIBS}
@@ -916,10 +912,6 @@ endif()
 if (onnxruntime_DEBUG_NODE_INPUTS_OUTPUTS)
   target_compile_definitions(onnxruntime_test_all PRIVATE DEBUG_NODE_INPUTS_OUTPUTS)
 endif()
-
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  target_link_libraries(onnxruntime_test_all PRIVATE onnxruntime_language_interop onnxruntime_pyop)
-endif()
 if (onnxruntime_USE_ROCM)
   if (onnxruntime_USE_COMPOSABLE_KERNEL)
     target_compile_definitions(onnxruntime_test_all PRIVATE USE_COMPOSABLE_KERNEL)
@@ -1057,10 +1049,6 @@ set(onnx_test_libs
   onnx_test_data_proto
   ${onnxruntime_EXTERNAL_LIBRARIES})
 
-if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-  list(APPEND onnx_test_libs onnxruntime_language_interop onnxruntime_pyop)
-endif()
-
 if (NOT IOS)
     onnxruntime_add_executable(onnx_test_runner ${onnx_test_runner_src_dir}/main.cc)
     if(MSVC)
@@ -1241,10 +1229,6 @@ if (NOT onnxruntime_ENABLE_TRAINING_TORCH_INTEROP)
     endif()
     set_target_properties(onnxruntime_perf_test PROPERTIES FOLDER "ONNXRuntimeTest")
 
-    if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS AND NOT onnxruntime_BUILD_SHARED_LIB)
-      target_link_libraries(onnxruntime_perf_test PRIVATE onnxruntime_language_interop onnxruntime_pyop)
-    endif()
-
     if (onnxruntime_USE_TVM)
       if (WIN32)
         target_link_options(onnxruntime_perf_test PRIVATE "/STACK:4000000")
@@ -1474,10 +1458,6 @@ endif()
       onnxruntime_flatbuffers
     )
 
-    if (onnxruntime_ENABLE_LANGUAGE_INTEROP_OPS)
-      list(APPEND ONNXRUNTIME_TEST_LIBS onnxruntime_language_interop onnxruntime_pyop)
-    endif()
-
     target_link_libraries(onnxruntime_test_trainer PRIVATE
       ${ONNXRUNTIME_TEST_LIBS}
       ${onnxruntime_EXTERNAL_LIBRARIES}