media: dvbsky: use the new dvb_module_probe() API

Instead of repeating countless times a complex logic, use
the new dvb_module_probe()/dvb_module_release(), simplifying
the module.

That reduced about 15% at the module's size:

   text	   data	    bss	    dec	    hex	filename
   7083	   1108	     12	   8203	   200b	old/drivers/media/usb/dvb-usb-v2/dvbsky.o
   5817	   1108	     12	   6937	   1b19	new/drivers/media/usb/dvb-usb-v2/dvbsky.o

Tested with a DVBSky S960C DVB-S2 tuner (0572:960c)
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>