[Mips][Disassembler] When disassembler meets cache/pref instructions for r6 it crashes as the access to operands array is out of range. This patch adds dedicated decoder method for R6 CACHE_HINT_DESC class that properly handles decoding of these instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227430 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed