[LLC]: llc_mac_hdr_init const arguments

Cleanup of LLC.  llc_mac_hdr_init can take constant arguments,
and it is defined twice once in llc_output.h that is otherwise unused.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Acked-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/llc/llc_output.c b/net/llc/llc_output.c
index b4d55b6..b4e668e 100644
--- a/net/llc/llc_output.c
+++ b/net/llc/llc_output.c
@@ -30,7 +30,8 @@
  *	Fills MAC header fields, depending on MAC type. Returns 0, If MAC type
  *	is a valid type and initialization completes correctly 1, otherwise.
  */
-int llc_mac_hdr_init(struct sk_buff *skb, unsigned char *sa, unsigned char *da)
+int llc_mac_hdr_init(struct sk_buff *skb,
+		     const unsigned char *sa, const unsigned char *da)
 {
 	int rc = 0;