serial: vt8500: Use of_device_get_match_data

Retrieve OF match data, it's better and cleaner to use
'of_device_get_match_data' over 'of_match_device'.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20210822032806.3256-4-tangbin@cmss.chinamobile.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>