Remove the form field from Mips16 instruction formats and set things

up so that we can apply the direct object emitter patch. This patch
should be a nop right now and it's test is to not break what is already
there.
 


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175126 91177308-0d34-0410-b5e6-96231b3b80d8