staging: emxx_udc: Remove unnecessary NULL checks

These pointers can't be NULL so I have removed the checks.

The checking was sort of problematic as well because it didn't make
sense.  In _nbu2ss_read_request_data() the && should have been ||.  In
nbu2ss_gad_get_frame() we know that "pgadget" is non-NULL and "udc" is
an offset from "pgadget" so it can't be NULL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>