V4L/DVB: tm6000: depends on IR_CORE

tm6000 uses IR interfaces, so it should depend on IR_CORE.

ERROR: "get_rc_map" [drivers/staging/tm6000/tm6000.ko] undefined!
ERROR: "ir_input_unregister" [drivers/staging/tm6000/tm6000.ko] undefined!
ERROR: "__ir_input_register" [drivers/staging/tm6000/tm6000.ko] undefined!

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>