feat: enable bitcode (#365)

Summary:
Bitcode is turned on by default in React Native and so, setting it here as well.

Changelog: [iOS] [Changed] - Upgraded JSI with a new HERMES_ENABLE_BITCODE flag

Pull Request resolved: facebook/hermes#365

Reviewed By: tmikov

Differential Revision: D23823228

Pulled By: Huxpro

fbshipit-source-id: d43638818a733f6a87b2f4a1ecadad8ea9c7a419

Author: grabbou

ReactCommon/jsi/jsi/CMakeLists.txt

@@ -21,6 +21,9 @@ elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "MSVC")
   # when they go out of scope due to exceptions.
   list(APPEND jsi_compile_flags "/EHsc")
 endif()
+if (HERMES_ENABLE_BITCODE)
+  list(APPEND jsi_compile_flags "-fembed-bitcode")
+endif ()
 target_compile_options(jsi PUBLIC ${jsi_compile_flags})
 
 install(DIRECTORY "${PROJECT_SOURCE_DIR}/API/jsi/" DESTINATION include