The function meson_uart_release_port() inappropriately try to
iounmap() a resource managed by devm_ioremap_nocache().
The function meson_uart_release_port() maybe called by uart_ioctl()
that means meson_uart_release_port() is not called from within a
probe or remove function, for safety, I convert iounmap() to
devm_iounmap().
Signed-off-by: NFiro Yang <firogm@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>