[X86][MS-InlineAsm] Extended support for variables / identifiers on memory / immediate expressions

Allow the proper recognition of Enum values and global variables inside ms inline-asm memory / immediate expressions, as they require some additional overhead and treated incorrect if doesn't early recognized.
supersedes D33278, D35774

Differential Revision: https://reviews.llvm.org/D37412

llvm-svn: 314493