sockev: change addrlen from int to socklen_t

Fix compilation warnings since socklen_t is unsigned. No functional
changes in this patch.

Change-Id: Ied68433fb966bc338b1fc0c3171c4443b809344f

sockev/src/sockev_cli.c

@@ -43,7 +43,8 @@ IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 int main(void)
 {
-	int skfd, addrlen, rc;
+	int skfd, rc;
+	socklen_t addrlen;
 	struct sockaddr_nl my_addr, src_addr;
 	struct nlmsghdr *nlh = NULL;
 	struct sknlsockevmsg *msg;