package/postgis: bump version to 3.1.2

package/postgis: bump version to 3.1.2

PostGIS 3.1.2
2021/05/21

 * Bug Fixes

  - #4871, TopoGeometry::geometry cast returns NULL for empty
           TopoGeometry objects (Sandro Santilli)
  - #4826, postgis_tiger_geocoder Better answers when no zip is provided
           (Regina Obe)
  - #4817, handle more complex compound coordinate dystems (Paul Ramsey)
  - #4842, Only do axis flips on CRS that have a "Lat" as the first column (Paul Ramsey)
  - Support recent Proj versions that have removed pj_get_release (Paul Ramsey)
  - #4835, Adjust tolerance for geodetic calculations (Paul Ramsey)
  - #4840, Improper conversion of negative geographic azimuth to positive (Paul Ramsey)
  - #4853, DBSCAN cluster not formed when recordset length equal to minPoints (Dan Baston)
  - #4863, Update bboxes after scale/affine coordinate changes (Paul Ramsey)
  - #4876, Fix raster issues related to PostgreSQL 14 tablefunc changes
           (Paul Ramsey, Regina Obe)
  - #4877, mingw64 PostGIS / PostgreSQL 14 compile (Regina Obe, Tom Lane)
  - #4838, Update to support Tiger 2020 (Regina Obe)
  - #4890, Change Proj cache lifetime to last as long as connection (Paul Ramsey)
  - #4845, Add Pg14 build support (Paul Ramsey)

Signed-off-by: Maxim Kochetkov <fido_max@inbox.ru>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>