Make Field.db_parameters() use db_type()

This reverts parts of ca9c3cd, which appear to have been made unintentionally.

It removes support for `db_type` to return the "CHECK (%s)" constraint suffix.
Internal code appears to use `db_parameters` for this.

Fixes #22260.

Conflicts:
	django/db/models/fields/__init__.py
Removed  and PostGIS  changes related to ticket #22001.