Drop fragment from openstreetmap.org URL

In an openstreetmap.org URL, if mlat and mlon query parameters are used, it’s unnecessary to repeat their values in the fragment. The zoom can be provided as another query parameter, so the fragment can be removed.

If the author remembers correctly, providing the fragment used to reset user’s chosen layer and overlays, since they’re stored in the fragment; though currently visiting any URL with mlat and mlon seems to reset them.