sms: Set bit 5 of I/O port B/Misc
sms: Set bit 5 of I/O port B/Misc

Documentation suggests that this bit is unused. It is always set on
SMS/GG hardware. It is always unset on Megadrive hardware.

Some homebrew games expect the bit to be set and won't work otherwise.

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