Mapper 28 (Action 53) seems to initialize wrong

[NovaSquirrel]

Action 53's mapper should power up with $c000-$ffff mapped to the last 16KB of the ROM. However, Mesen initializes all mapper registers to zero, so as soon as UpdateState() gets called, the first 16KB is put in $c000-$ffff because of a zero outer bank.

[negativeExponent]

REGS have to be initialized to 0xff, then call UpdateState() in init instead of SelectPrgPage()