tc: filter: fix default 'protocol all' on little-endian platforms

when specifiying filters without 'protocol' keyword, tc will
default to 'protocol all'.

Unfortunately, this missed a byte-ordering conversion.
diff --git a/tc/tc_filter.c b/tc/tc_filter.c
index 919c57c..4e55812 100644
--- a/tc/tc_filter.c
+++ b/tc/tc_filter.c
@@ -73,7 +73,7 @@
 	req.t.tcm_family = AF_UNSPEC;
 
 	if (cmd == RTM_NEWTFILTER && flags & NLM_F_CREATE)
-		protocol = ETH_P_ALL;
+		protocol = htons(ETH_P_ALL);
 
 	while (argc > 0) {
 		if (strcmp(*argv, "dev") == 0) {