V4L/DVB (7653): tuner-xc2028: drop the severity of version reporting

tuner-xc2028.c
 - Drop the severity level of the xc3028 version reporting, since it's
   only of interest to developers and user's don't need to have it show up
   in their dmesg output every time they change the channel.

Signed-off-by: Devin Heitmueller <devin.heitmueller@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>