Make all the conditional Mips 16 branches get initially set for the

short form. Constant islands will expand them if they are out of range.
Since there is not direct object emitter at this time, it does not
have any material affect because the assembler sorts this out. But we
need to know for the actual constant island work. We track the difference
by putting # 16 inst in the comments.

llvm-svn: 194766