SDL: audio: take first reported device if no default was specified.

SDL Commits
1 
From b60a56d368afe4401740a522bcccca70ea13e0f4 Mon Sep 17 00:00:00 2001
From: "Ryan C. Gordon" <[EMAIL REDACTED]>
Date: Mon, 3 Jul 2023 11:38:17 -0400
Subject: [PATCH] audio: take first reported device if no default was
 specified.

---
 src/audio/SDL_audio.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/audio/SDL_audio.c b/src/audio/SDL_audio.c
index 77f5c2d86c80..56e7ac113b52 100644
--- a/src/audio/SDL_audio.c
+++ b/src/audio/SDL_audio.c
@@ -579,7 +579,13 @@ int SDL_InitAudio(const char *driver_name)
         current_audio.default_capture_device_id = default_capture->instance_id;
     }
 
-    // !!! FIXME: if a default is zero but there are devices available, should we just pick the first one?
+    // If no default was _ever_ specified, just take the first device we see, if any.
+    if (!current_audio.default_output_device_id && (current_audio.output_devices != NULL)) {
+        current_audio.default_output_device_id = current_audio.output_devices->instance_id;
+    }
+    if (!current_audio.default_capture_device_id && (current_audio.capture_devices != NULL)) {
+        current_audio.default_capture_device_id = current_audio.capture_devices->instance_id;
+    }
 
     return 0;
 }