Fix crash with HTCP (#319)

diff --git a/usrsctplib/netinet/sctp_cc_functions.c b/usrsctplib/netinet/sctp_cc_functions.c
index 788e4db..6323829 100755
--- a/usrsctplib/netinet/sctp_cc_functions.c
+++ b/usrsctplib/netinet/sctp_cc_functions.c
@@ -1962,7 +1962,7 @@
 static inline uint32_t
 htcp_ccount(struct htcp *ca)
 {
-	return (htcp_cong_time(ca)/ca->minRTT);
+	return (ca->minRTT == 0 ? htcp_cong_time(ca) : htcp_cong_time(ca)/ca->minRTT);
 }
 
 static inline void