V4L/DVB: Missing statement in drivers/media/dvb/frontends/cx22700.c

Stumbled over this because of coverity (id #492),
seems like we are missing a return statement here and fail
to do proper bounds checking. If this assumption is false
we should at least change the identation to make it clear

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>