A few misc fixes:
A few misc fixes:

- Ensure we read the entire ROM in with one fread call.
  (TODO: loop until error)
- Ensure cart type value in header is within our name array bounds.
  (Nobody's ever tried HuC1 carts, huh?  Instant crash in debug.)
- Cast read_size correctly to avoid overflow.

foxkit-us/supergameherm,supergameherm/supergameherm