V4L/DVB (6897): xc2028: ignore HAS_IF during specific S-Code type searches

If we are selecting the S-Code firmware to load by name, then we must mask
off the HAS_IF bit during the search.

Signed-off-by: Chris Pascoe <c.pascoe@itee.uq.edu.au>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>