Merging r355825:

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r355825 | petarj | 2019-03-11 07:13:31 -0700 (Mon, 11 Mar 2019) | 10 lines

[MIPS][microMIPS] Add a pattern to match TruncIntFP

A pattern needed to match TruncIntFP was missing. This was causing multiple
tests from llvm test suite to fail during compilation for micromips.

Patch by Mirko Brkusanin.

Differential Revision: https://reviews.llvm.org/D58722

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llvm-svn: 358936