Use default UDP ring buffer size of 65536 for clients

We should probably create a specific function for setting the
recv buffer anyway. UDP sockets does not need to bind (listen)
to be able to call recvfrom. This is especially useful for clients
who just call set_send_address and start communicating with a server.

(cherry picked from commit 93368571326e3472522669b76998f58aed78864f)

drivers/unix/packet_peer_udp_posix.cpp

@@ -158,7 +158,7 @@ void PacketPeerUDPPosix::close() {
 		::close(sockfd);
 	sockfd = -1;
 	sock_type = IP::TYPE_NONE;
-	rb.resize(8);
+	rb.resize(16);
 	queue_count = 0;
 }
 
@@ -269,7 +269,7 @@ PacketPeerUDPPosix::PacketPeerUDPPosix() {
 	queue_count = 0;
 	peer_port = 0;
 	sock_type = IP::TYPE_NONE;
-	rb.resize(8);
+	rb.resize(16);
 }
 
 PacketPeerUDPPosix::~PacketPeerUDPPosix() {

platform/windows/packet_peer_udp_winsock.cpp

@@ -152,7 +152,7 @@ void PacketPeerUDPWinsock::close() {
 		::closesocket(sockfd);
 	sockfd = -1;
 	sock_type = IP::TYPE_NONE;
-	rb.resize(8);
+	rb.resize(16);
 	queue_count = 0;
 }
 
@@ -278,7 +278,7 @@ PacketPeerUDPWinsock::PacketPeerUDPWinsock() {
 	queue_count = 0;
 	peer_port = 0;
 	sock_type = IP::TYPE_NONE;
-	rb.resize(8);
+	rb.resize(16);
 }
 
 PacketPeerUDPWinsock::~PacketPeerUDPWinsock() {