[media] tc358743: fix register i2c_rd/wr function fix

The below mentioned fix contains a small but severe bug,
fix it to make the driver work again.

Fixes: 3538aa6e ("[media] tc358743: fix register i2c_rd/wr functions")

Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>