Make easier to use MariaDB 10.4

Just add the following 2 lines in a SR:

[mariadb]
location = ${mariadb-10.4:location}

component/mariadb/buildout.cfg

@@ -26,10 +26,10 @@ extends =
 parts =
   mariadb
 
-[mariadb]
+[mariadb-10.4]
 recipe = slapos.recipe.cmmi
 shared = true
-url = https://downloads.mariadb.org/f/mariadb-${:version}/source/mariadb-${:version}.tar.gz/from/http%3A//fr.mirror.babylon.network/mariadb/?serve
+url = https://archive.mariadb.org//mariadb-${:version}/source/mariadb-${:version}.tar.gz
 version = 10.4.14
 md5sum = 9801120ae8acb33904ab4a3366a7714f
 location = @@LOCATION@@
@@ -129,9 +129,9 @@ environment =
 
 ### XXX keep using mariadb 10.3.22 because 10.4 cause crash
 ### (we just override here for easier revert)
-[mariadb]
+[mariadb-10.3]
+<= mariadb-10.4
 version = 10.3.22
-url = https://downloads.mariadb.org/f/mariadb-10.3.22/source/mariadb-10.3.22.tar.gz/from/http%3A//ftp.hosteurope.de/mirror/archive.mariadb.org/?serve
 md5sum = f712a5e6fde038d0c9c6d2a2cd88b84e
 pre-configure =
   set -e '\bSET(PLUGIN_AUTH_PAM YES)' cmake/build_configurations/mysql_release.cmake
@@ -145,14 +145,6 @@ post-install =
   mkdir -p ${:location}/include/wsrep &&
   cp -p wsrep/wsrep_api.h ${:location}/include/wsrep
 
-[mroonga-mariadb]
-pre-configure =
-  rm -rf fake_mariadb_source
-  mkdir -p fake_mariadb_source
-  cd fake_mariadb_source
-  ln -s ${mariadb:location}/wsrep-lib
-  cp -a ${mariadb:location}/include/mysql/server include
-  cp -a include/private sql
-  chmod -R a+w include sql # so that buildout can delete this compile-dir after install
-  mkdir -p ${:plugin-dir}
+[mariadb]
+location = ${mariadb-10.3:location}
 ### /XXX keep using mariadb 10.3.22 because 10.4 cause crash