MDEV-6284: Revert commit af03ba84 partially for systemd

This version of Debian packaging does not yet install systemd scripts,
so revert that part to the CMakeLists.txt based hack.

CMakeLists.txt

@@ -435,6 +435,12 @@ CONFIGURE_FILE(
     ${CMAKE_SOURCE_DIR}/cmake/info_macros.cmake.in
     ${CMAKE_BINARY_DIR}/info_macros.cmake @ONLY)
 
+IF(DEB)
+  CONFIGURE_FILE(
+    ${CMAKE_SOURCE_DIR}/debian/mariadb-server-10.2.install.in
+    ${CMAKE_SOURCE_DIR}/debian/mariadb-server-10.2.install)
+ENDIF(DEB)
+
 # Handle the "INFO_*" files.
 INCLUDE(${CMAKE_BINARY_DIR}/info_macros.cmake)
 # Source: This can be done during the cmake phase, all information is

debian/mariadb-server-10.2.install → debian/mariadb-server-10.2.install.in

@@ -63,3 +63,4 @@ usr/share/mysql/mysql_system_tables.sql
 usr/share/mysql/mysql_system_tables_data.sql
 usr/share/mysql/mysql_test_data_timezone.sql
 usr/share/mysql/wsrep_notify
+@SYSTEMD_DEB_FILES@

debian/rules

@@ -156,7 +156,10 @@ override_dh_installlogrotate-arch:
 # Start mysql at sequence number 19 before 20 where apache, proftpd etc gets
 # started which might depend on a running database server.
 override_dh_installinit-arch:
+	if [ -x /usr/bin/dh_systemd_enable -a -f debian/mariadb-server-10.2/lib/systemd/system/mariadb.service ]; then dh_systemd_enable -pmariadb-server-10.2 mariadb.service; fi
+	if [ -x /usr/bin/dh_systemd_enable -a -f debian/mariadb-server-10.2/lib/systemd/system/mariadb@.service ]; then dh_systemd_enable --no-enable -pmariadb-server-10.2 mariadb@.service; fi
 	dh_installinit --name=mysql -- defaults 19 21
+	if [ -x /usr/bin/dh_systemd_start -a -f debian/mariadb-server-10.2/lib/systemd/system/mariadb.service ]; then dh_systemd_start -pmariadb-server-10.2 --restart-after-upgrade mariadb.service; fi
 
 override_dh_installcron-arch:
 	dh_installcron --name mysql-server