Mips assembler: formatting and comment changes.

This patch should not have any functional changes. 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179737 91177308-0d34-0410-b5e6-96231b3b80d8
[mips] DSP-ASE move from HI/LO register instructions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179739 91177308-0d34-0410-b5e6-96231b3b80d8