netlink: kconfig: move mmap i/o into netlink kconfig

Currently, in menuconfig, Netlink's new mmaped IO is the very first
entry under the ``Networking support'' item and comes even before
``Networking options'':

  [ ]   Netlink: mmaped IO
  Networking options  --->
  ...

Lets move this into ``Networking options'' under netlink's Kconfig,
since this might be more appropriate. Introduced by commit ccdfcc39
(``netlink: mmaped netlink: ring setup'').
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/Kconfig

@@ -23,15 +23,6 @@ menuconfig NET
 
 if NET
 
-config NETLINK_MMAP
-	bool "Netlink: mmaped IO"
-	help
-	  This option enables support for memory mapped netlink IO. This
-	  reduces overhead by avoiding copying data between kernel- and
-	  userspace.
-
-	  If unsure, say N.
-
 config WANT_COMPAT_NETLINK_MESSAGES
 	bool
 	help

net/netlink/Kconfig

@@ -2,6 +2,15 @@
 # Netlink Sockets
 #
 
+config NETLINK_MMAP
+	bool "NETLINK: mmaped IO"
+	---help---
+	  This option enables support for memory mapped netlink IO. This
+	  reduces overhead by avoiding copying data between kernel- and
+	  userspace.
+
+	  If unsure, say N.
+
 config NETLINK_DIAG
 	tristate "NETLINK: socket monitoring interface"
 	default n