[MIRParser] Allow register class names in the form of integer/scalar

Summary:
The current code cannot handle register class names like 'i32', which is
a valid register class name in WebAssembly. This patch removes special
handling for integer/scalar/pointer type parsing and treats them as
normal identifiers.

Reviewers: thegameg

Subscribers: jfb, dschuff, sbc100, jgravelle-google, sunfish, llvm-commits

Differential Revision: https://reviews.llvm.org/D45948

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331586 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed