mariadb: upgrade from 5.5.38 to 39

Upgrade mariadb from 5.5.38 to 5.5.39. Previous upgrade made a lot of
work, so it is easy this time.

Signed-off-by: Kai Kang <kai.kang@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>