[QNN EP] Disable early termination in GetCapability (microsoft#18140)

[QNN EP] Disable early termination in GetCapability if there are
multiple partition and context binary enabled

### Description
QNN EP context binary cache feature only support single partition for
now. We have early termination in GetCapability.
After the PR microsoft#17764.
There's no Level 1 optimization any more for the 1st GetCapability.
Graph transformer EnsureUniqueDQForNodeUnit is not applied. So if
there's initializer -> DQ -> shared by multiple node unit. The node is
not identified as node unit group. QNN EP report many not supported
nodes because of this in the 1st GetCapability call.
The 2nd GetCapability still works normally.
Disable the early termination in GetCapability, delay the decision to
Compile.

onnxruntime/core/providers/qnn/qnn_execution_provider.cc

@@ -404,10 +404,6 @@ QNNExecutionProvider::GetCapability(const onnxruntime::GraphViewer& graph_viewer
     }
   }
 
-  if (num_of_partitions > 1) {
-    ORT_ENFORCE(!context_cache_enabled_, "Only support single partition for context cache feature.");
-  }
-
   const auto summary_msg = MakeString("Number of partitions supported by QNN EP: ", num_of_partitions,
                                       ", number of nodes in the graph: ", num_nodes_in_graph,
                                       ", number of nodes supported by QNN: ", num_of_supported_nodes);
@@ -485,7 +481,7 @@ Status QNNExecutionProvider::Compile(const std::vector<FusedNodeAndGraph>& fused
 
   bool is_ctx_file_exist = qnn_cache_model_handler_->GetIsContextCacheFileExists();
   if (is_qnn_ctx_model || (context_cache_enabled_ && is_ctx_file_exist)) {
-    ORT_ENFORCE(fused_nodes_and_graphs.size() == 1, "Only support single partition for context cache feature.");
+    ORT_RETURN_IF(fused_nodes_and_graphs.size() != 1, "Only support single partition for context cache feature.");
     std::unique_ptr<qnn::QnnModel> qnn_model = std::make_unique<qnn::QnnModel>(logger, qnn_backend_manager_.get());
     // Load and execute from cached context if exist
     ORT_RETURN_IF_ERROR(qnn_cache_model_handler_->LoadQnnCtxFromOnnxModel(graph_viewer,
@@ -509,7 +505,7 @@ Status QNNExecutionProvider::Compile(const std::vector<FusedNodeAndGraph>& fused
 
   ORT_RETURN_IF_ERROR(CompileFromOrtGraph(fused_nodes_and_graphs, node_compute_funcs, logger));
   if (context_cache_enabled_ && !is_qnn_ctx_model) {
-    ORT_ENFORCE(fused_nodes_and_graphs.size() == 1, "Only support single partition for context cache feature.");
+    ORT_RETURN_IF(fused_nodes_and_graphs.size() != 1, "Only support single partition for context cache feature.");
     uint64_t buffer_size(0);
     auto context_buffer = qnn_backend_manager_->GetContextBinaryBuffer(buffer_size);
     ORT_RETURN_IF_ERROR(qnn_cache_model_handler_->GenerateCtxCacheOnnxModel(context_buffer.get(),