systemd-autofs-restart.sh: fix issue with removed check_fs_type reference

"Check_fs_type" helper was repalce by "get_fs_type".
This reference is a silly mistake.

Signed-off-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>