net/l2tp: 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: "David S. Miller" <[e-mail]>
Signed-off-by: Kees Cook <[e-mail]>
Acked-by: David S. Miller <[e-mail]>

net/l2tp/Kconfig

···
 	  will be called l2tp_debugfs.
 
 config L2TP_V3
-	bool "L2TPv3 support (EXPERIMENTAL)"
-	depends on EXPERIMENTAL && L2TP
+	bool "L2TPv3 support"
+	depends on L2TP
 	help
 	  Layer Two Tunneling Protocol Version 3