Fix a few warnings and remove extra white spaces

modules/demux/mkv.cpp

@@ -478,7 +478,7 @@ block_t *block_zlib_decompress( vlc_object_t *p_this, block_t *p_in_block ) {
 /**
  * Helper function to print the mkv parse tree
  */
-static void MkvTree( demux_t & demuxer, int i_level, char *psz_format, ... )
+static void MkvTree( demux_t & demuxer, int i_level, const char *psz_format, ... )
 {
     va_list args;
     if( i_level > 9 )
@@ -487,7 +487,7 @@ static void MkvTree( demux_t & demuxer, int i_level, char *psz_format, ... )
         return;
     }
     va_start( args, psz_format );
-    static char *psz_foo = "|   |   |   |   |   |   |   |   |   |";
+    static const char psz_foo[] = "|   |   |   |   |   |   |   |   |   |";
     char *psz_foo2 = (char*)malloc( ( i_level * 4 + 3 + strlen( psz_format ) ) * sizeof(char) );
     strncpy( psz_foo2, psz_foo, 4 * i_level );
     psz_foo2[ 4 * i_level ] = '+';
@@ -603,10 +603,10 @@ typedef struct
     vlc_bool_t      b_silent;
 
     /* informative */
-    char         *psz_codec_name;
-    char         *psz_codec_settings;
-    char         *psz_codec_info_url;
-    char         *psz_codec_download_url;
+    const char   *psz_codec_name;
+    const char   *psz_codec_settings;
+    const char   *psz_codec_info_url;
+    const char   *psz_codec_download_url;
 
     /* encryption/compression */
     int                    i_compression_type;
@@ -4079,7 +4079,7 @@ void matroska_segment_c::ParseTrackEntry( KaxTrackEntry *m )
         }
         else  if( MKV_IS_ID( l, KaxTrackType ) )
         {
-            char *psz_type;
+            const char *psz_type;
             KaxTrackType &ttype = *(KaxTrackType*)l;
 
             switch( uint8(ttype) )
@@ -4261,20 +4261,17 @@ void matroska_segment_c::ParseTrackEntry( KaxTrackEntry *m )
                                 }
                             }
                         }
-
                         else
                         {
                             MkvTree( sys.demuxer, 5, "Unknown (%s)", typeid(*l3).name() );
                         }
                     }
-                    
                 }
                 else
                 {
                     MkvTree( sys.demuxer, 4, "Unknown (%s)", typeid(*l2).name() );
                 }
             }
-                
         }
 //        else if( EbmlId( *l ) == KaxCodecSettings::ClassInfos.GlobalId )
 //        {