playlist: log errors during loadPlaylist()

Don't call command_error() if loading a song from the playlist fails.
This may result in assertion failures, since command_error() may be
called more than once.

src/command.c

@@ -591,7 +591,7 @@ handle_load(struct client *client, G_GNUC_UNUSED int argc, char *argv[])
 {
 	enum playlist_result result;
 
-	result = loadPlaylist(client, argv[1]);
+	result = loadPlaylist(argv[1]);
 	return print_playlist_result(client, result);
 }
 

src/playlist.c

@@ -1333,7 +1333,7 @@ int PlaylistInfo(struct client *client, const char *utf8file, int detail)
 	return 0;
 }
 
-enum playlist_result loadPlaylist(struct client *client, const char *utf8file)
+enum playlist_result loadPlaylist(const char *utf8file)
 {
 	GPtrArray *list;
 
@@ -1352,8 +1352,7 @@ enum playlist_result loadPlaylist(struct client *client, const char *utf8file)
 				p++;
 			}
 			if ((addToPlaylist(temp, NULL)) != PLAYLIST_RESULT_SUCCESS) {
-				command_error(client, ACK_ERROR_PLAYLIST_LOAD,
-					      "can't add file \"%s\"", temp2);
+				g_warning("can't add file \"%s\"", temp2);
 			}
 			free(temp2);
 		}

src/playlist.h

@@ -126,7 +126,7 @@ enum playlist_result swapSongsInPlaylist(unsigned song1, unsigned song2);
 
 enum playlist_result swapSongsInPlaylistById(unsigned id1, unsigned id2);
 
-enum playlist_result loadPlaylist(struct client *client, const char *utf8file);
+enum playlist_result loadPlaylist(const char *utf8file);
 
 bool getPlaylistRepeatStatus(void);