sdl2-compat: Fixed memory leak.

SDL Commits
1 
From 708145331a91a796b0de3ece463bb588f13ca81e Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Wed, 29 Jan 2025 14:02:24 -0500
Subject: [PATCH] Fixed memory leak.

Reference Issue #255.
---
 src/sdl2_compat.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/sdl2_compat.c b/src/sdl2_compat.c
index 433cf2c..fc81c31 100644
--- a/src/sdl2_compat.c
+++ b/src/sdl2_compat.c
@@ -6255,9 +6255,7 @@ Display_IndexToID(int displayIndex)
 {
     SDL_DisplayID displayID;
     int count = 0;
-    const SDL_DisplayID *list;
-
-    list = SDL3_GetDisplays(&count);
+    SDL_DisplayID *list = SDL3_GetDisplays(&count);
 
     if (list == NULL || count == 0) {
         SDL3_SetError("no displays");
@@ -6270,6 +6268,8 @@ Display_IndexToID(int displayIndex)
     }
 
     displayID = list[displayIndex];
+    SDL3_free(list);
+
     return displayID;
 }