Cleanup rpm-distro mariadb install

We have lib/databases/mysql which is installing databases, remove it
from the bulk package lists.

Split is_fedora (fedora & centos8 -- soon) to install mariadb-server
and mariadb-devel to retain status-quo.

On suse this seems to be a meta-package

 'mariadb-server' not found in package names. Trying capabilities.

so split that out.  It seems it has never been installing the -devel
package, and things work (presumably clients are coming from wheels so
don't need to build against it).

Change-Id: I86433318e8f76c40c5c792b795411a5c9d8351d3

lib/databases/mysql

@@ -175,7 +175,10 @@ EOF
     # Install mysql-server
     if is_oraclelinux; then
         install_package mysql-community-server
-    elif is_fedora || is_suse; then
+    elif is_fedora; then
+        install_package mariadb-server mariadb-devel
+        sudo systemctl enable $MYSQL_SERVICE_NAME
+    elif is_suse; then
         install_package mariadb-server
         sudo systemctl enable $MYSQL_SERVICE_NAME
     elif is_ubuntu; then