Corrects MOVE -(An), SR/CCR, which was not previously decrementing.
Corrects MOVE -(An), SR/CCR, which was not previously decrementing.

Also adds a safety check against other instances of the same error. There seem to be none.

TomHarte/CLK,TomHarte/CLK,TomHarte/CLK,TomHarte/CLK,TomHarte/CLK