✨ Enable MPS build on macOS by default.

Author: jathu

tools/cmake/preset/pybind.cmake

@@ -22,6 +22,7 @@ set_overridable_option(EXECUTORCH_BUILD_EXTENSION_FLAT_TENSOR ON)
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   set_overridable_option(EXECUTORCH_BUILD_COREML ON)
+  set_overridable_option(EXECUTORCH_BUILD_MPS ON)
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
   set_overridable_option(EXECUTORCH_BUILD_COREML ON)
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows" OR CMAKE_SYSTEM_NAME STREQUAL "WIN32")