fix(mfreadnam): restore get_entries_from_namefile behavior when none found

Author: wpbonelli

flopy/utils/mfreadnam.py

@@ -326,6 +326,9 @@ def get_entries_from_namefile(
                     if extension.lower() == ext.lower():
                         entries.append((filename, ll[0], ll[1], status))
 
+    if len(entries) < 1:
+        entries.append((None, None, None, None))
+
     return entries