SDL_net: SDLNet_GetLocalAddresses now accepts a NULL argument.

SDL Commits
1 
From ea878c0a9a4eede65dba9e4128a3ad6df208b1b8 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Mon, 25 Sep 2023 23:37:28 -0400
Subject: [PATCH] SDLNet_GetLocalAddresses now accepts a NULL argument.

---
 SDL_net.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/SDL_net.c b/SDL_net.c
index ca7b3eb..f23af89 100644
--- a/SDL_net.c
+++ b/SDL_net.c
@@ -599,6 +599,11 @@ SDLNet_Address **SDLNet_GetLocalAddresses(int *num_addresses)
     int count = 0;
     SDLNet_Address **retval = NULL;
 
+    int dummy_addresses;
+    if (!num_addresses) {
+        num_addresses = &dummy_addresses;
+    }
+
     *num_addresses = 0;
 
 #ifdef __WINDOWS__