Skip redundant file/dir tests

Marlin/src/sd/cardreader.cpp

@@ -154,12 +154,13 @@ char *createFilename(char * const buffer, const dir_t &p) {
 // Return 'true' if the item is a folder or G-code file
 //
 bool CardReader::is_dir_or_gcode(const dir_t &p) {
-  uint8_t pn0 = p.name[0];
+  //uint8_t pn0 = p.name[0];
 
-  if ( pn0 == DIR_NAME_FREE || pn0 == DIR_NAME_DELETED  // Clear or Deleted entry
-    || pn0 == '.' || longFilename[0] == '.'             // Hidden file
-    || !DIR_IS_FILE_OR_SUBDIR(&p)                       // Not a File or Directory
-    || (p.attributes & DIR_ATT_HIDDEN)                  // Hidden by attribute
+  if ( (p.attributes & DIR_ATT_HIDDEN)                  // Hidden by attribute
+    // When readDir() > 0 these must be false:
+    //|| pn0 == DIR_NAME_FREE || pn0 == DIR_NAME_DELETED  // Clear or Deleted entry
+    //|| pn0 == '.' || longFilename[0] == '.'             // Hidden file
+    //|| !DIR_IS_FILE_OR_SUBDIR(&p)                       // Not a File or Directory
   ) return false;
 
   flag.filenameIsDir = DIR_IS_SUBDIR(&p);               // We know it's a File or Folder