SDL_net: voipchat: Clamp datagram payload to 1200 instead of 1500.

SDL Commits
1 
From cc307c2653bffc8cfc3ee26ee6c80fa28ece2d72 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Wed, 27 Sep 2023 12:12:37 -0400
Subject: [PATCH] voipchat: Clamp datagram payload to 1200 instead of 1500.

Apparently some common routers will drop packets that are larger than
1278 bytes...gave myself a little wiggle room here.
---
 examples/voipchat.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/examples/voipchat.c b/examples/voipchat.c
index c7d5bff..0b8c552 100644
--- a/examples/voipchat.c
+++ b/examples/voipchat.c
@@ -358,10 +358,7 @@ int main(int argc, char **argv)
     renderer = SDL_CreateRenderer(window, NULL, 0);
     SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
 
-    max_datagram = 1500;
-    if (max_datagram > sizeof (scratch_area)) {
-        max_datagram = sizeof (scratch_area);
-    }
+    max_datagram = SDL_min(1200, (int) sizeof (scratch_area));
 
     run_voipchat(argc, argv);