Codechange: Replace C-style casts to size_t with static_cast. (#12455)

* Codechange: Replace C-style casts to size_t with static_cast.

This touches only simple value-type casts.

* Codechange: Replace static_cast<size_t>(-1) with SIZE_MAX

Co-authored-by: Rubidium <rubidium@openttd.org>

src/network/core/udp.cpp

@@ -133,7 +133,7 @@ void NetworkUDPSocketHandler::ReceivePackets()
 
 			/* If the size does not match the packet must be corrupted.
 			 * Otherwise it will be marked as corrupted later on. */
-			if (!p.ParsePacketSize() || (size_t)nbytes != p.Size()) {
+			if (!p.ParsePacketSize() || static_cast<size_t>(nbytes) != p.Size()) {
 				Debug(net, 1, "Received a packet with mismatching size from {}", address.GetAddressAsString());
 				continue;
 			}