Fix finding extension modules ending in "module.so" with the VFS importer

direct/src/showbase/VFSImporter.py

@@ -76,8 +76,7 @@ class VFSImporter:
             if desc[2] != imp.C_EXTENSION:
                 continue
 
-            filename = Filename(path)
-            filename.setExtension(desc[0][1:])
+            filename = Filename(path + desc[0])
             vfile = vfs.getFile(filename, True)
             if vfile:
                 return VFSLoader(dir_path, vfile, filename, FTExtensionModule,