[media] lg2160: Fix a few warnings

[media] lg2160: Fix a few warnings

drivers/media/dvb/frontends/lg2160.c: In function ‘lg216x_read_ucblocks’:
drivers/media/dvb/frontends/lg2160.c:1336:1: warning: label ‘fail’ defined but not used [-Wunused-label]
drivers/media/dvb/frontends/lg2160.c:1325:6: warning: unused variable ‘ret’ [-Wunused-variable]
drivers/media/dvb/frontends/lg2160.c:1324:23: warning: unused variable ‘state’ [-Wunused-variable]
drivers/media/dvb/frontends/lg2160.c: In function ‘lg216x_set_ensemble’:
drivers/media/dvb/frontends/lg2160.c:420:23: warning: ‘reg’ may be used uninitialized in this function [-Wuninitialized]

Cc: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>