[media] xc5000: change filename to production/redistributable xc5000c firmware

The original xc5000c driver support was based on a beta version of the
firmware, and there were no redistribution rights.  Change over to using
the release version, for which freely redistributable firmware can be
found here:

http://kernellabs.com/firmware/xc5000/README.xc5000c
http://kernellabs.com/firmware/xc5000/dvb-fe-xc5000c-4.1.30.7.fw

Thanks to Ramon Cazares from Cresta Technology for making the firmware
available as well as working out the licensing issues.

[mchehab@redhat.com: Fix a merge conflict with the patch that added support
 for MODULE_FIRMWARE() macro]
Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Cc: Michael Krufky <mkrufky@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>