llvm-cov: Fix a misuse of ArrayRef::slice I introduced in r217430

It appears this code was completely untested, so using ArrayRef wrong
didn't break anything obvious.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217476 91177308-0d34-0410-b5e6-96231b3b80d8
[MIPS] Add aliases for sync instruction used by Octeon CPU

This commit adds aliases for the sync instruction (synciobdma,
syncs, syncw, syncws) which are used by the Octeon CPU.

Reviewed by D. Sanders

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217477 91177308-0d34-0410-b5e6-96231b3b80d8