BOOLEAN
IsFatVolume(
  IN  PPACKED_BOOT_SECTOR Buffer
  );

Routine Description:

    This routine looks at the buffer passed in which contains the FAT boot
    sector and determines whether or not it represents an actual FAT boot
    sector.

Arguments:

    Buffer - Pointer to buffer containing potential boot block.

Return Value:

    The function returns TRUE if the buffer contains a recognizable FAT boot
    sector, otherwise it returns FALSE.