Enable Android CI build stages to run in parallel. (#21314)

Enable Android CI build stages to run in parallel to possibly reduce total build time.

tools/ci_build/github/azure-pipelines/android-x86_64-crosscompile-ci-pipeline.yml

@@ -49,6 +49,7 @@ stages:
 # Separate stage for building CPU vs NNAPI as we only want CodeQL to run on one of them so we don't get duplicate
 # issues for code that is built in both. We pick NNAPI as that includes the NNAPI EP code.
 - stage: BUILD_CPU_STAGE
+  dependsOn: []
   variables:
     Codeql.Enabled: false
   jobs:
@@ -130,6 +131,7 @@ stages:
     - template: templates/clean-agent-build-directory-step.yml
 
 - stage: BUILD_NNAPI_STAGE
+  dependsOn: []
   variables:
     Codeql.ProjectConfigPath: .github/workflows
     Codeql.Enabled: true