Make disassembled x86 register indices reflect their size.

Make disassembled x86 register indices reflect their size.
This doesn't handle high byte register accesses. It also highlights the fact that address size isn't actually being calculated, and that the size a microop uses needs to be overridable from the microassembly.

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extra : convert_revision : d495ac4f5756dc55a5f71953ff6963b3c030e6cb