meta-patches: remove 0003-fix-postgresql_openstack-PGDATA-install-error.patch

meta-patches: remove 0003-fix-postgresql_openstack-PGDATA-install-error.patch

This is fixed in meta-starlingx by commit:
===========================================================
commit d4ee39187200cb73726694cd3ece35f55e3adde1
Author: Babak Sarashki <babak.sarashki@windriver.com>
Date:   Mon Sep 28 22:18:57 2020 -0700

    postgres: Fix install error on none existent file

    Required to complete postgres build and  ported from upstream
    meta-cloud-services.  This commit to be removed when moving to
    to dunfell or later.

    Upstream commit: 8516070112019bd7b3a5c41eb55a042808a13089
    Closes-Bug: 1899552
    Change-Id: I9ec82e41567a41734a0b10445e4ada661693c4d7
    Signed-off-by: Babak Sarashki <babak.sarashki@windriver.com>
===========================================================

Issue-ID: INF-213

Signed-off-by: Jackie Huang <jackie.huang@windriver.com>
Change-Id: I5ecaee0004bf4101398cfdb5b72ccb6c0f7f8681