[media] V4L2: sh_vou: add I2C build dependency

The sh_vou driver needs CONFIG_I2C or CONFIG_I2C_MODULE to build, add the
respective dependency.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>