Adjust a couple of error cases in camdd(8).

Adjust a couple of error cases in camdd(8).

usr.sbin/camdd/camdd.c:
	In camdd_probe_file(), fix an error case after fstat where
	we were bailing out and leaving two lines of cleanup code
	unexecuted.  Instead, just goto bailout_error.

	In camdd_probe_pass(), fail if the sector size is 0.

Sponsored by:	Spectra Logic
MFC after:	3 days