fix duplicate id issue refs https://github.com/geoadmin/mf-chsdi3/issues...

.../308

Hi Loic

this pull request should solve the duplicate id issues described in https://github.com/geoadmin/mf-chsdi3/issues/308

The other issue 'NOTICE: LWGEOM_gist_joinsel called with incorrect join type' has been solved in the view definition.