Fix compilation of trunk with --enable-symbol-visibility following r2…

…7375.

git-svn-id: http://svn.mythtv.org/svn/trunk@27377 7dbf422c-18fa-0310-86e9-fd20926502f2

mythtv/libs/libmyth/audiooutpututil.h

@@ -5,7 +5,7 @@ using namespace std;
 #include "mythverbose.h"
 #include "audiooutputsettings.h"
 
-class AudioOutputUtil
+class MPUBLIC AudioOutputUtil
 {
  public:
     static bool has_hardware_fpu();