src/player/mpvadapter: fix compatibility with mpv 0.38.0

Since mpv client API 2.3 introduced with mpv 0.38.0, the loadfile
command now takes an additional argument, which breaks audio clip
generation. To fix this, optionally add the additional (and ignored)
argument to the loadfile command depending on the loaded mpv version.

src/player/mpvadapter.cpp

@@ -591,12 +591,18 @@ void MpvAdapter::open(const QString     &file,
 
     QByteArray filename = file.toUtf8();
     QByteArray opts = options.join(',').toUtf8();
+    char *argOpts = opts.isEmpty() ? NULL : opts.data();
 
-    const char *args[5] = {
+    /* Since mpv client API 2.3 (mpv 0.38.0) "loadfile" places an extra argument before the options,
+       so we need to conditionally re-arrange the arguments array */
+    bool isApi23 = mpv_client_api_version() >= MPV_MAKE_VERSION(2, 3);
+
+    const char *args[] = {
         "loadfile",
         filename,
         append ? "append-play" : "replace",
-        opts.isEmpty() ? NULL : opts.data(),
+        isApi23 ? "0"     : argOpts,
+        isApi23 ? argOpts : NULL,
         NULL
     };
 
@@ -918,11 +924,15 @@ QString MpvAdapter::tempAudioClip(
     optionCmd += QString("start=%1").arg(start, 0, 'f', 3).toUtf8();
     optionCmd += QString(",end=%1").arg(end, 0, 'f', 3).toUtf8();
     optionCmd += QString(",aid=%1").arg(aid).toUtf8();
+    char *argOpts = optionCmd.isEmpty() ? NULL : optionCmd.data();
+
+    bool isApi23 = mpv_client_api_version() >= MPV_MAKE_VERSION(2, 3);
     const char *args[] = {
         "loadfile",
         input,
         "replace",
-        optionCmd.isEmpty() ? NULL : optionCmd.data(),
+        isApi23 ? "0"     : argOpts,
+        isApi23 ? argOpts : NULL,
         NULL
     };