Remove support for opensuse

We haven't been testing the distro for a while in CI, e.g. in
Tempest, the jobs on opensuse15 haven't been executed for a year
now.
Therefore the patch removes opensuse support from devstack.

Closes-Bug: #2002900
Change-Id: I0f5e4c644e2d14d1b8bb5bc0096d1469febe5fcc
diff --git a/lib/databases/postgresql b/lib/databases/postgresql
index 4f0a5a0..b21418b 100644
--- a/lib/databases/postgresql
+++ b/lib/databases/postgresql
@@ -32,7 +32,7 @@
         # Get ruthless with mysql
         apt_get purge -y postgresql*
         return
-    elif is_fedora || is_suse; then
+    elif is_fedora; then
         uninstall_package postgresql-server
     else
         return
@@ -66,11 +66,6 @@
         pg_dir=`find /etc/postgresql -name pg_hba.conf|xargs dirname`
         pg_hba=$pg_dir/pg_hba.conf
         pg_conf=$pg_dir/postgresql.conf
-    elif is_suse; then
-        pg_hba=/var/lib/pgsql/data/pg_hba.conf
-        pg_conf=/var/lib/pgsql/data/postgresql.conf
-        # initdb is called when postgresql is first started
-        sudo [ -e $pg_hba ] || start_service postgresql
     else
         exit_distro_not_supported "postgresql configuration"
     fi
@@ -107,7 +102,7 @@
     if [[ "$INSTALL_DATABASE_SERVER_PACKAGES" == "True" ]]; then
         if is_ubuntu; then
             install_package postgresql
-        elif is_fedora || is_suse; then
+        elif is_fedora; then
             install_package postgresql-server
             if is_fedora; then
                 sudo systemctl enable postgresql