Add 1 to the X register, not affecting carry

Operation

X - 1 -> X

Table

INX | Increment Index Register X by 1
================================================

X - 1 -> X                       N V - B D I Z C
                                 + - - - - - + -

addressing       assembler    opc  bytes  cycles
------------------------------------------------
implied          INX           E8    1      2

Flags

• Negative: 1 if bit 7 of result is 1; 0 otherwise
• Zero: 1 if result is zero; 0 otherwise