V4L/DVB: tm6000: add send and recv function

Split the i2c send and receive functions on separate functions

[mchehab@redhat.com: CodingStyle and fix the logic for more than 2 read values]
Signed-off-by: Stefan Ringel <stefan.ringel@arcor.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>