SDL: audio: Check for unlikely failure case in WAV loaded.

SDL Commits
1 
From 7ee24599276861edf45db4a4779c61cd0341f690 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Tue, 30 May 2023 01:09:21 -0400
Subject: [PATCH] audio: Check for unlikely failure case in WAV loaded.

I don't think this can fail at the moment, but if WaveCheckFormat goes
out of sync with this switch statement at some point, this seems like
a good failsafe.
---
 src/audio/SDL_wave.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/audio/SDL_wave.c b/src/audio/SDL_wave.c
index e7e5fc032739..759d34d9e1f6 100644
--- a/src/audio/SDL_wave.c
+++ b/src/audio/SDL_wave.c
@@ -2058,6 +2058,8 @@ static int WaveLoad(SDL_RWops *src, WaveFile *file, SDL_AudioSpec *spec, Uint8 *
             return SDL_SetError("Unexpected %u-bit PCM data format", (unsigned int)format->bitspersample);
         }
         break;
+    default:
+        return SDL_SetError("Unexpected data format");
     }
 
     /* Report the end position back to the cleanup code. */