[stella] Fastest(?) paddle reading

[Thomas Jentzsch]

This is a slight modification of my previous paddle reading code.

Old code:
   bit INPT0    ; 3
   bpl .save    ; 2/3
   .byte $2c    ; 4/0	
.save:
   sty paddle   ; 0/3
Total: 9 cycles

New code:
   bit INPT0    ; 3
   bmi .save+1  ; 2/3
.save:
   sty paddle   ; 3/2    paddle has to be at the address of an 1 byte, 2  
cycles opcode, e.g. $ea (NOP)
Total: 8 cycles, 1 cycle saved :)

Have fun!
Thomas