Staging: easycap: Add dependencies to Kconfig

The "depends on" line was inadvertently omitted from the inaugural patch.
Signed-off-by: Mike Thomas <rmthomas@sciolus.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/easycap/Kconfig

 config EASYCAP
 	tristate "EasyCAP USB ID 05e1:0408 support"
+	depends on USB && VIDEO_DEV
 
 	---help---
 	  This is an integrated audio/video driver for EasyCAP cards with