[X86] Avoid using high register trick for test instruction

Summary:
It seems it's main effect is to create addition copies when values are inr register that do not support this trick, which increase register pressure and makes the code bigger.

Reviewers: craig.topper, niravd, spatel, hfinkel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D42646

llvm-svn: 323888