Add missing netinet/in.h (for freebsd)

Signed-off-by: Adrien Gallouët <adrien@gallouet.fr>

src/main.c

@@ -15,6 +15,7 @@
 #include <stdio.h>
 #include <sys/socket.h>
 #include <sys/time.h>
+#include <netinet/in.h>
 
 #include <arpa/inet.h>
 #include <netdb.h>