[media] bttv: make remote controls of devices with i2c ir decoder working

Request module ir-kbd-i2c if an i2c ir decoder is detected.
Tested with device "Hauppauge WinTV Theatre" (model 37284 rev B421).

Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>