Allow the second opcode info table to be 8, 16, or 32-bits as needed to...

Allow the second opcode info table to be 8, 16, or 32-bits as needed to represent additional fragments. This recovers some space on ATT X86 syntax and PowerPC which only need 40-bits instead of 48-bits. This also increases ARM to 64-bits to fully encode all of its operands.

llvm-svn: 163880