[LLParser] Simplify type checking in ParseArithmetic and ParseUnaryOp.
Summary:
These methods previously took a 0, 1, or 2 to indicate what types were allowed, but the 0 encoding which meant both fp and integer types has been unused for years. Its leftover from when add/sub/mul used to be shared between int and fp
Simplify it by changing it to just a bool to distinquish int and fp.
Reviewers: spatel, dblaikie, jyknight, arsenm
Reviewed By: spatel
Subscribers: wdng, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61561
llvm-svn: 359986