Install NXP and OpenVINO backends, top-level CMake targets (#13673)

Make the top-level backends, extensions, and kernels targets
installable. See #12949. Add
CMake export directives for NXP and OpenVINO, which are needed to
support the exportable top-level targets.

I've also removed the apple and llm/apple extensions from the
executorch_extensions target. From what I understand, these won't be
consumed this way, as they are build via apple frameworks. There is some
installation complexity to make it work with install, so I'm inclined to
skip it if it won't be used. Will check with Anthony in the comments.

Author: GregoryComer

CMakeLists.txt

@@ -582,7 +582,6 @@ endif()
 
 if(EXECUTORCH_BUILD_EXTENSION_APPLE)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/extension/apple)
-  list(APPEND _executorch_extensions apple_extension)
 endif()
 
 if(EXECUTORCH_BUILD_EXTENSION_DATA_LOADER)
@@ -649,7 +648,6 @@ endif()
 
 if(EXECUTORCH_BUILD_EXTENSION_LLM_APPLE)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/extension/llm/apple)
-  list(APPEND _executorch_extensions extension_llm_apple)
 endif()
 
 if(EXECUTORCH_BUILD_EXTENSION_RUNNER_UTIL)
@@ -968,6 +966,10 @@ else()
 endif()
 target_link_libraries(executorch_kernels INTERFACE ${_executorch_kernels})
 
+install(TARGETS executorch_backends executorch_extensions executorch_kernels
+        EXPORT ExecuTorchTargets
+)
+
 if(EXECUTORCH_BUILD_EXECUTOR_RUNNER)
   # Baseline libraries that executor_runner will link against.
   set(_executor_runner_libs executorch extension_evalue_util

backends/nxp/CMakeLists.txt

@@ -3,15 +3,19 @@
 # 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
-)
+set(_common_include_directories ${CMAKE_CURRENT_SOURCE_DIR}/../../..)
 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}
+  executorch_delegate_neutron
+  PRIVATE ${_common_include_directories}
+          ${PROJECT_SOURCE_DIR}/runtime/core/portable_type/c10
+)
+install(
+  TARGETS executorch_delegate_neutron
+  EXPORT ExecuTorchTargets
+  DESTINATION lib
 )

backends/openvino/CMakeLists.txt

@@ -38,7 +38,7 @@ add_library(openvino_backend STATIC .)
 target_compile_options(openvino_backend PRIVATE -frtti -fexceptions)
 
 # Include Executorch directories
-target_include_directories(openvino_backend PUBLIC ${COMMON_INCLUDE_DIRS})
+target_include_directories(openvino_backend PRIVATE ${COMMON_INCLUDE_DIRS})
 
 # Link OpenVINO and ExecuteTorch core libraries
 target_link_libraries(
@@ -78,4 +78,10 @@ if(EXECUTORCH_BUILD_OPENVINO_EXECUTOR_RUNNER)
 endif()
 
 # Install OpenVINO backend library to the lib directory
-install(TARGETS openvino_backend DESTINATION lib)
+install(
+  TARGETS openvino_backend
+  EXPORT ExecuTorchTargets
+  DESTINATION lib
+  INCLUDES
+  DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}
+)