[TableGen] Add a knob for MCOperandInfo expansion in gen-instr-info

Control the MCOperandInfo expansion with `-instr-info-expand-mi-operand-info`.
For X86, this would make it possible to see memory operand type e.g.:
```
    /* MOV8rm */
    GR8, i8mem,
    /* MOV8rm_NOREX */
    GR8_NOREX, i8mem_NOREX,
```

The intended use is a follow-up diff D126116 (`getMemOperandSize`).

Reviewed By: skan

Differential Revision: https://reviews.llvm.org/D127932