[media] davinci: add i2c Kconfig dependencies

All the davinci media drivers are using the i2c framework, and
fail to build if that is ever disabled, e.g.:

media/platform/davinci/vpif_display.c: In function 'vpif_probe':
media/platform/davinci/vpif_display.c:1298:14: error: implicit declaration of function 'i2c_get_adapter' [-Werror=implicit-function-declaration]

This adds explicit Kconfig dependencies so we don't see the
driver options if I2C is turned off.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>