media: tuners: qt1010: replace BUG_ON with a regular error

BUG_ON is unnecessary here, and in addition it confuses smatch.
Replacing this with an error return help resolve this smatch
warning:

drivers/media/tuners/qt1010.c:350 qt1010_init() error: buffer overflow 'i2c_data' 34 <= 34

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>