ieee802154: cleanup ieee802154_be64_to_le64

This patch cleanups the ieee802154_be64_to_le64 function. This patch
removes an unnecessary temporary variable.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/mac802154.h b/include/net/mac802154.h
index 8506478..c5c6445 100644
--- a/include/net/mac802154.h
+++ b/include/net/mac802154.h
@@ -19,6 +19,7 @@
 #include <net/af_ieee802154.h>
 #include <linux/ieee802154.h>
 #include <linux/skbuff.h>
+#include <linux/unaligned/memmove.h>
 
 #include <net/cfg802154.h>
 
@@ -233,9 +234,7 @@
  */
 static inline void ieee802154_be64_to_le64(void *le64_dst, const void *be64_src)
 {
-	__le64 tmp = (__force __le64)swab64p(be64_src);
-
-	memcpy(le64_dst, &tmp, IEEE802154_EXTENDED_ADDR_LEN);
+	__put_unaligned_memmove64(swab64p(be64_src), le64_dst);
 }
 
 /**