net: core: move mac_pton() to lib/net_utils.c

Since we have at least one user of this function outside of CONFIG_NET
scope, we have to provide this function independently. The proposed
solution is to move it under lib/net_utils.c with corresponding
configuration variable and select wherever it is needed.

Signed-off-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index cec074b..35a9f080 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -12,6 +12,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/moduleparam.h>
+#include <linux/kernel.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/string.h>