fix signed warning

libc/inet/inet_net.c

@@ -48,7 +48,7 @@ __inet_network(const char *cp)
 	register in_addr_t val, base, n;
 	register char c;
 	in_addr_t parts[4], *pp = parts;
-	register int i;
+	register unsigned int i;
 
 again:
 	/*