[media] cx24120: don't initialize a var that won't be used

As reported by smatch:
drivers/media/dvb-frontends/cx24120.c: In function 'cx24120_message_send':
drivers/media/dvb-frontends/cx24120.c:368:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable]
  int ret, ficus;
      ^

The values written by cx24120 are never checked. So, remove the
check here too. That's said, the best would be to do the reverse,
but globally: to properly handle the error codes.

Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Signed-off-by: Patrick Boettcher <patrick.boettcher@posteo.de>