Fix bluray playback if mounting path is a symbolic link

Some distributions (such as Ubuntu) symlink /media/cdrom0 to /media/cdrom. Decryption would fail if trying to play bd:/media/cdrom.
We know determine the actual canonical path

Fix #10340 (part 2)

mythtv/libs/libmythtv/bdringbuffer.cpp

@@ -275,6 +275,16 @@ bool BDRingBuffer::OpenFile(const QString &lfilename, uint retry_ms)
     safefilename = lfilename;
     filename = lfilename;
 
+        // clean path filename
+    QString filename = QDir(QDir::cleanPath(lfilename)).canonicalPath();
+    if (filename.isEmpty())
+    {
+        LOG(VB_GENERAL, LOG_ERR, LOC +
+            QString("%1 nonexistent").arg(lfilename));
+        filename = lfilename;
+    }
+    safefilename = filename;
+
     LOG(VB_GENERAL, LOG_INFO, LOC + QString("Opened BDRingBuffer device at %1")
             .arg(filename.toLatin1().data()));