Update the signature of net_set_low_water() from int fo socklen_t.

src/common/net.c

@@ -168,7 +168,7 @@ int readn(int fd, void *buf, size_t nbytes)
 	return(n);
 }
 
-int net_set_low_water(int sock, int size)
+int net_set_low_water(int sock, socklen_t size)
 {
 	if (setsockopt(sock, SOL_SOCKET, SO_RCVLOWAT,
 		       (const void *) &size, sizeof(size)) < 0) {

src/common/net.h

@@ -41,6 +41,7 @@
 #define _NET_H
 
 #include <stdint.h>
+#include <sys/socket.h>
 
 #include "src/common/macros.h"
 
@@ -59,7 +60,7 @@ extern int net_accept_stream(int fd);
 
 /* set low water mark on socket
  */
-extern int net_set_low_water(int sock, int size);
+extern int net_set_low_water(int sock, socklen_t size);
 
 /* set keep alive time on socket */
 extern int net_set_keep_alive(int sock);