[media] dvb: Use DVBFE_ALGO_HW where applicable

[media] dvb: Use DVBFE_ALGO_HW where applicable

The dvb_frontend.c core defines a FE_ALGO_HW symbol that it is
never used. Also, both cx24123 returns 1 to get_algo() callback
instead of using DVBFE_ALGO_HW.

Probably, those are some left overs from some code cleanup.

Let's stop returning magic numbers and use the proper macro
value.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>