Fixed PostGIS remove_field implementation

Fixed bad code introduced in 2f9d157.

Author: claudep

django/contrib/gis/db/backends/postgis/schema.py

@@ -92,12 +92,12 @@ def add_field(self, model, field):
 
  def remove_field(self, model, field):
  from django.contrib.gis.db.models.fields import GeometryField
- if not isinstance(field, GeometryField) or self.connection.ops.spatial_version < (2, 0):
+ if not isinstance(field, GeometryField) or self.connection.ops.spatial_version > (2, 0):
  super(PostGISSchemaEditor, self).remove_field(model, field)
-
- self.execute(
- self.sql_drop_geometry_column % {
- "table": self.geo_quote_name(model._meta.db_table),
- "column": self.geo_quote_name(field.column),
- }
- )
+ else:
+  self.execute(
+  self.sql_drop_geometry_column % {
+  "table": self.geo_quote_name(model._meta.db_table),
+  "column": self.geo_quote_name(field.column),
+  }
+  )