[PATCH] Emit the ARM build attributes ABI_PCS_wchar_t and ABI_enum_size.

[Oliver Stannard]

> you're never using, nor testing this... x3

I was following the example of the other build attributes (e.g. the position independent code ones), including all values specified in the ABI addenda, even if we do not use them.

http://reviews.llvm.org/D4213