[X86] Make the instructions that use AdSize16/32/64 co-exist together without...

[X86] Make the instructions that use AdSize16/32/64 co-exist together without using mode predicates.

This is necessary to allow the disassembler to be able to handle AdSize32 instructions in 64-bit mode when address size prefix is used.

Eventually we should probably also support 'addr32' and 'addr16' in the assembler to override the address size on some of these instructions. But for now we'll just use special operand types that will lookup the current mode size to select the right instruction.

llvm-svn: 225075