V4L/DVB (5791): Fix Kbuild for kbd-ir-i2c

Potentially, all board types with I2C and IR support can use an i2c
based IR. Currently, the driver is selected only if bt848 or saa7134
boards are selected.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>