V4L/DVB (7910): usb: input layer dependency fixes

testing of the -tip tree found the following build failures on
2.6.26-rc3:

  drivers/built-in.o: In function `ttusb_dec_disconnect':
  ttusb_dec.c:(.text+0xa2c95): undefined reference to `input_unregister_device'

  drivers/built-in.o: In function `dvb_usb_read_remote_control':
  dvb-usb-remote.c:(.text+0xa6a94): undefined reference to `input_event'

with this config:

  http://redhat.com/~mingo/misc/config-Tue_May_20_03_48_57_CEST_2008.bad

these are due to the media/dvb/usb layer having dependencies on INPUT
functionality, without having that spelled out in the Kconfig file.

this patch makes that dependency explicit (for the drivers affected),
which solves the build error.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/dvb/dvb-usb/Kconfig

 config DVB_USB
 	tristate "Support for various USB DVB devices"
-	depends on DVB_CORE && USB && I2C
+	depends on DVB_CORE && USB && I2C && INPUT
 	depends on HOTPLUG	# due to FW_LOADER
 	select FW_LOADER
 	help

drivers/media/dvb/ttusb-dec/Kconfig

 config DVB_TTUSB_DEC
 	tristate "Technotrend/Hauppauge USB DEC devices"
-	depends on DVB_CORE && USB
+	depends on DVB_CORE && USB && INPUT
 	depends on HOTPLUG	# due to FW_LOADER
 	select FW_LOADER
 	select CRC32