fix typo for params, should be param in line 1016

My IDE gives a syntax error that params is not defined in  XMLConverter.py line 1016
  
105 else:
106           dprint(__name__, 0, "MEDIAPATH - element not found: {0}", params)
107            res = 'FILE_NOT_FOUND'  # not found?

I checked, looks like should be 'param'? Seem barely fall in this path though, kind of typo? Anway, please check and merge if needed.