drivers/rpmsg: remove depends on CONFIG_EXPERIMENTAL

The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

CC: Ohad Ben-Cohen <ohad@wizery.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>

drivers/rpmsg/Kconfig

-menu "Rpmsg drivers (EXPERIMENTAL)"
+menu "Rpmsg drivers"
 
 # RPMSG always gets selected by whoever wants it
 config RPMSG
 	tristate
 	select VIRTIO
-	depends on EXPERIMENTAL
 
 endmenu