INES Mapper 202

Implemented in BizHawk as of commit f72875b584abd79201ad9d3d0131fa5afcf0c429

 ========================
 =  Mapper 202          =
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Used for the 150-in-1 pirate cart

Registers:
$8000-FFFF: A~[.... .... .... O..O]
              [.... .... .... RRRM]

O = PRG Mode, if 3, will use 32 PRG mode, else 16
R = page registers, used for both chr 8k banks, and prg banks (in both 16k and 32k modes)
M = Mirroring, 0 = Vertical, 1 = Horizontal

CHR Setup:

                   $0000   $0400   $0800   $0C00   $1000   $1400   $1800   $1C00 
                  +-------------------------------+-------------------------------+
CHR-ROM:          |                             { 0 }                             |
                  +-------------------------------+-------------------------------+

PRG Setup:
------------------------------

32k Mode:

$8000     $A000     $C000     $E000
+-------------------------------------+
|                 {0}                 |
+-------------------------------------+

16k Mode:

In 16k mode both regions are mapped to the same PRG bank

$8000     $A000     $C000     $E000     
+--------------------------------------+
|        {0}        |       {0}        |
+--------------------------------------+