slip: Fix hexdump print

The fragment count value was incorrectly printed. All
the values > 9 had their last digit chopped off.

Change-Id: I8304b8047baa97995c3927809e4616653c87928b
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>

drivers/slip/slip.c

diff --git a/drivers/slip/slip.c b/drivers/slip/slip.c
index fc84de5..3499da8 100644
--- a/drivers/slip/slip.c
+++ b/drivers/slip/slip.c
@@ -198,10 +198,10 @@
 		SYS_LOG_DBG("sent data %d bytes",
 			    frag->len + net_nbuf_ll_reserve(buf));
 		if (frag->len + ll_reserve) {
-			char msg[7 + 1];
+			char msg[8 + 1];
 
-			snprintf(msg, sizeof(msg), "<slip %d", frag_count++);
-			msg[7] = '\0';
+			snprintf(msg, sizeof(msg), "<slip %2d", frag_count++);
+
 			hexdump(msg, net_nbuf_ll(buf),
 				frag->len + net_nbuf_ll_reserve(buf),
 				net_nbuf_ll_reserve(buf));
@@ -347,10 +347,10 @@
 			int count = 0;
 
 			while (bytes && frag) {
-				char msg[7 + 1];
+				char msg[8 + 1];
 
-				snprintf(msg, sizeof(msg), ">slip %d", count);
-				msg[7] = '\0';
+				snprintf(msg, sizeof(msg), ">slip %2d", count);
+
 				hexdump(msg, frag->data, frag->len, 0);
 
 				frag = frag->frags;