net: re-ordered includes in ng_netreg + ng_pktbuf

sys/net/crosslayer/ng_netreg/ng_netreg.c

@@ -16,9 +16,9 @@
 #include <string.h>
 
 #include "clist.h"
+#include "utlist.h"
 #include "net/ng_netreg.h"
 #include "net/ng_nettype.h"
-#include "utlist.h"
 
 #define _INVALID_TYPE(type) (((type) <= NG_NETTYPE_UNDEF) || ((type) >= NG_NETTYPE_NUMOF))
 

sys/net/crosslayer/ng_pktbuf/ng_pktbuf.c

@@ -23,11 +23,10 @@
 
 #include "clist.h"
 #include "mutex.h"
-#include "net/ng_nettype.h"
-#include "net/ng_pkt.h"
 #include "utlist.h"
-
 #include "net/ng_pktbuf.h"
+#include "net/ng_nettype.h"
+#include "net/ng_pkt.h"
 
 #include "_pktbuf_internal.h"