Merging r328944:

Merging r328944:

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r328944 | chandlerc | 2018-04-01 14:47:55 -0700 (Sun, 01 Apr 2018) | 4 lines

[x86] Expose more of the condition conversion routines in the public API
for X86's instruction information. I've now got a second patch under
review that needs these same APIs. This bit is nicely orthogonal and
obvious, so landing it. NFC.
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_60@332564 91177308-0d34-0410-b5e6-96231b3b80d8