Introducing NXP Neutron runtime (pytorch#10563)

### Summary

Introducing NXP Neutron runtime.

cc @digantdesai @JakeStevens @robert-kalmar

Author: jirioc

.github/workflows/trunk.yml

@@ -271,6 +271,36 @@ jobs:
           exit 1
         fi
 
+  nxp-build-test:
+    name: nxp-build-test
+    uses: pytorch/test-infra/.github/workflows/linux_job_v2.yml@main
+    permissions:
+      id-token: write
+      contents: read
+    with:
+      runner: linux.2xlarge
+      docker-image: executorch-ubuntu-22.04-arm-sdk
+      submodules: 'recursive'
+      ref: ${{ github.event_name == 'pull_request' && github.event.pull_request.head.sha || github.sha }}
+      timeout: 90
+      script: |
+        # The generic Linux job chooses to use base env, not the one setup by the image
+        CONDA_ENV=$(conda env list --json | jq -r ".envs | .[-1]")
+        conda activate "${CONDA_ENV}"
+
+        # Build
+        cmake -DEXECUTORCH_BUILD_NXP_NEUTRON=ON -Bcmake-out .
+        cmake --build cmake-out --target executorch_delegate_neutron --config Release
+
+        # Build check for the neutron backend library
+        lib_neutron="cmake-out/backends/nxp/libexecutorch_delegate_neutron.a"
+        if [ -f $lib_neutron ]; then
+            echo "Neutron backend library built."
+        else
+            echo "Neutron backend library not found!"
+            exit 1
+        fi
+
   test-coreml-delegate:
     name: test-coreml-delegate
     uses: pytorch/test-infra/.github/workflows/macos_job.yml@main

CMakeLists.txt

@@ -496,6 +496,10 @@ if(EXECUTORCH_BUILD_CADENCE)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backends/cadence)
 endif()
 
+if(EXECUTORCH_BUILD_NXP_NEUTRON)
+  add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backends/nxp)
+endif()
+
 if(EXECUTORCH_BUILD_COREML)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backends/apple/coreml)
 endif()

backends/nxp/CMakeLists.txt

@@ -0,0 +1,18 @@
+# Copyright 2024 NXP
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+set(
+  _common_include_directories 
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../..
+  ${CMAKE_CURRENT_SOURCE_DIR}/../../runtime/core/portable_type/c10
+)
+add_compile_definitions(C10_USING_CUSTOM_GENERATED_MACROS)
+
+set(_neutron_sources ${CMAKE_CURRENT_SOURCE_DIR}/runtime/NeutronBackend.cpp )
+
+add_library(executorch_delegate_neutron STATIC ${_neutron_sources})
+target_include_directories(
+  executorch_delegate_neutron PUBLIC ${_common_include_directories}
+)