FAT_CACHED doesn't reference Device ID

[LIV2]

FAT_CACHED doesn't reference the device we've cached a FAT sector from, if we read a file from Disk A and attempt to read a file from Disk B it may think the FAT sector required is already cached, causing the system to follow the wrong cluster chain or have other unexpected behavior

MHMON/src/fat.inc

Line 348 in 0ec8dfc

@OK: m_copy16 NEXTSECTOR, FAT_CACHED