z80: flag_x and flag_y for cp
z80: flag_x and flag_y for cp

For these instructions, the undocumented flags are set from the operand

JoppyFurr/Snepulator,JoppyFurr/Snepulator,JoppyFurr/Snepulator,JoppyFurr/Snepulator,JoppyFurr/Snepulator,JoppyFurr/Snepulator