playlist/(Ext)M3u: use strchug_fast()

src/playlist/ExtM3uPlaylistPlugin.cxx

@@ -125,8 +125,7 @@ ExtM3uPlaylist::NextSong()
 			continue;
 		}
 
-		while (*line_s != 0 && g_ascii_isspace(*line_s))
-			++line_s;
+		line_s = strchug_fast(line_s);
 	} while (line_s[0] == '#' || *line_s == 0);
 
 	song = Song::NewRemote(line_s);

src/playlist/M3uPlaylistPlugin.cxx

@@ -22,10 +22,9 @@
 #include "PlaylistPlugin.hxx"
 #include "SongEnumerator.hxx"
 #include "Song.hxx"
+#include "util/StringUtil.hxx"
 #include "TextInputStream.hxx"
 
-#include <glib.h>
-
 class M3uPlaylist final : public SongEnumerator {
 	TextInputStream tis;
 
@@ -54,9 +53,7 @@ M3uPlaylist::NextSong()
 			return NULL;
 
 		line_s = line.c_str();
-
-		while (*line_s != 0 && g_ascii_isspace(*line_s))
-			++line_s;
+		line_s = strchug_fast(line_s);
 	} while (line_s[0] == '#' || *line_s == 0);
 
 	return Song::NewRemote(line_s);