SDL_mixer: Fix huge memory waste with resampled sound samples

SDL Commits
1 
From 5eb80dc561de7762f2b6c4631791cd027b25c1b6 Mon Sep 17 00:00:00 2001
From: Markus Mittendrein <[EMAIL REDACTED]>
Date: Sun, 20 Nov 2022 16:15:33 +0100
Subject: [PATCH] Fix huge memory waste with resampled sound samples
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At the moment SDL’s sample rate conversion requests a really big buffer which is 4x the necessary size when the target format is 16 bit integer.
In some cases we even saw buffers 6x the necessary size. This change ensures that after format conversion only the necessary buffer size is kept.
---
 src/mixer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mixer.c b/src/mixer.c
index d713df50..67c14551 100644
--- a/src/mixer.c
+++ b/src/mixer.c
@@ -860,7 +860,7 @@ Mix_Chunk *Mix_LoadWAV_RW(SDL_RWops *src, int freesrc)
             return(NULL);
         }
 
-        chunk->abuf = wavecvt.buf;
+        chunk->abuf = SDL_realloc(wavecvt.buf, wavecvt.len_cvt);
         chunk->alen = wavecvt.len_cvt;
         wavfree = 0;
     }