Revert "[NFC][Codegen][X86][AArch64][ARM][PowerPC] Add test coverage for...

Revert "[NFC][Codegen][X86][AArch64][ARM][PowerPC] Add test coverage for "add-of-inc" vs "sub-of-not""

Some test failures i don't have a moment to investigate.

This reverts commit r364930.

llvm-svn: 364939