MDEV-30818 invalid ssl prevents bootstrap

in bootstrap the server reads stdin and does not listen to network.
it won't use ssl anyway

mysql-test/main/bootstrap.result

@@ -61,5 +61,8 @@ truncate table mysql.plugin;
 # MDEV-13397 MariaDB upgrade fail when using default_time_zone
 #
 #
+# MDEV-30818 invalid ssl prevents bootstrap
+#
+#
 # End of 10.3 tests
 #

mysql-test/main/bootstrap.test

@@ -119,6 +119,11 @@ truncate table mysql.plugin;
 --echo #
 --exec $MYSQLD_BOOTSTRAP_CMD --default-time-zone=Europe/Moscow < $test_bootstrap >> $MYSQLTEST_VARDIR/tmp/bootstrap.log 2>&1
 
+--echo #
+--echo # MDEV-30818 invalid ssl prevents bootstrap
+--echo #
+--exec $MYSQLD_BOOTSTRAP_CMD --ssl-ca=/dev/nonexistent < $test_bootstrap >> $MYSQLTEST_VARDIR/tmp/bootstrap.log 2>&1
+
 --echo #
 --echo # End of 10.3 tests
 --echo #

sql/mysqld.cc

@@ -5026,7 +5026,10 @@ static void init_ssl()
     {
       sql_print_error("Failed to setup SSL");
       sql_print_error("SSL error: %s", sslGetErrString(error));
-      unireg_abort(1);
+      if (!opt_bootstrap)
+        unireg_abort(1);
+      opt_use_ssl = 0;
+      have_ssl= SHOW_OPTION_DISABLED;
     }
     if (global_system_variables.log_warnings > 0)
     {