Render motorcar=* the same as access=*

Currently the standard style renders highways tagged with permissive and destination differently. Given that most uses, particularly of access=destination are actually wrong (excludes access far all, including pedestrians for example), it would seem to be sensible to render at least the most of the time correct motorcar=destination and motor_vehicle=destination the same or drop the special rendering alltogether. motor_vehicle and motorcycle tags are missing from the osm2pgsql style file so thats not possible at this point in time without a lot of effort) , 

Note motorcar=no might be a candidate for rendering the same as access=no, however this should only be done on roads that commonaly are open to cars. 

The pull request is untested.