So the debugger can show them during stepping.
The fmt_* functions now take a PPCDisasmContext instead of just the ctx->instr_str so that they can alter the context.
Some fmt_* functions have an alternate (e.g. fmt_twoop_in for fmt_twoop) to indicate a difference in input/output registers.
The mtsrin and mfsrin instructions use a register to indicate which sr register to use.
The string instructions may affect multiple registers but only the first is included in the list.
Removed some extra blank lines.
Fixes:
lscbx: Add r0 check.
mftb: Do simplified if the spr is illegal. Maybe should do illegal opcode instead?
