[PATCH] dvb: avoid building empty built-in.o

Don't build empty built-in.o when DVB/V4L is not configured.  Thanks to Sam
Ravnborg and Keith Owens.
Signed-off-by: NJohannes Stezenbach <js@linuxtv.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

drivers/media/Makefile

@@ -2,4 +2,7 @@
 # Makefile for the kernel multimedia device drivers.
 #
 
-obj-y        := video/ radio/ dvb/ common/
+obj-y := common/
+obj-$(CONFIG_VIDEO_DEV) += video/
+obj-$(CONFIG_VIDEO_DEV) += radio/
+obj-$(CONFIG_DVB)       += dvb/