get rid of numerous gcc-4 warnings
diff --git a/libipq/libipq.c b/libipq/libipq.c
index a25ad4c..658af97 100644
--- a/libipq/libipq.c
+++ b/libipq/libipq.c
@@ -122,7 +122,8 @@
                                     unsigned char *buf, size_t len,
                                     int timeout)
 {
-	int addrlen, status;
+	unsigned int addrlen;
+	int status;
 	struct nlmsghdr *nlh;
 
 	if (len < sizeof(struct nlmsgerr)) {