[media] gspca/sn9c20x: Fix support for mt9m001 (mi1300) sensor
Support for mt9m001 (mi1300) is broken:
- Table is incomplete;
- Only one resolution is currently supported by the driver;
- Resolution is incomplete;
- it complains about broken JPEG headers.
Use the same init found on em28xx driver, and properly report the
output format as 8-bits GRAY.