Remove --basedir arg from systemd startup scripts

The arg was introduced as part of 75bcf1f9
to fix a SELinux problem caused by mysqld_safe accessing files it should
not be via the my_which function.

The root cause for this was fixed in 10.3, via
355ee687 which eliminated the my_which
function from mysqld_safe entirely. Thus, in 10.3, this --basedir flag
is not necessary.

support-files/mariadb.service.in

@@ -86,9 +86,7 @@ ExecStartPre=/bin/sh -c "[ ! -e @bindir@/galera_recovery ] && VAR= || \
 # Use the [Service] section and Environment="MYSQLD_OPTS=...".
 # This isn't a replacement for my.cnf.
 # _WSREP_NEW_CLUSTER is for the exclusive use of the script galera_new_cluster
-# Note: we set --basedir to prevent probes that might trigger SELinux alarms,
-# per bug https://bugzilla.redhat.com/show_bug.cgi?id=547485
-ExecStart=@sbindir@/mysqld $MYSQLD_OPTS --basedir=@prefix@ $_WSREP_NEW_CLUSTER $_WSREP_START_POSITION
+ExecStart=@sbindir@/mysqld $MYSQLD_OPTS $_WSREP_NEW_CLUSTER $_WSREP_START_POSITION
 
 # Unset _WSREP_START_POSITION environment variable.
 ExecStartPost=/bin/sh -c "systemctl unset-environment _WSREP_START_POSITION"

support-files/mariadb@.service.in

@@ -103,12 +103,9 @@ ExecStartPre=/bin/sh -c "[ ! -e @bindir@/galera_recovery ] && VAR= || \
 # This isn't a replacement for my.cnf.
 # _WSREP_NEW_CLUSTER is for the exclusive use of the script galera_new_cluster
 
-# Note: we set --basedir to prevent probes that might trigger SELinux alarms,
-# per bug https://bugzilla.redhat.com/show_bug.cgi?id=547485
-#
 # Note: Place $MYSQLD_OPTS at the very end for its options to take precedence.
 
-ExecStart=@sbindir@/mysqld --defaults-file=@sysconf2dir@/my%I.cnf --basedir=@prefix@ \
+ExecStart=@sbindir@/mysqld --defaults-file=@sysconf2dir@/my%I.cnf \
   $_WSREP_NEW_CLUSTER $_WSREP_START_POSITION%I $MYSQLD_OPTS
 # Alternate: (remove ConditionPathExists above)
 # use [mysqld.INSTANCENAME] as sections in my.cnf