Emit the ARM build attributes ABI_PCS_wchar_t and ABI_enum_size.

Emit the ARM build attributes ABI_PCS_wchar_t and ABI_enum_size based on
module flags metadata.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211349 91177308-0d34-0410-b5e6-96231b3b80d8