mxser: cleanup Gpci_uart_info struct

The Gpci_uart_info structure contains up to tripled information and
chose weird types for the members. Deduplicate the members and choose
proper types for the data -- everything can be u8 except baud rate.
There, we use speed_t, which is used in this context.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-6-jslaby@suse.cz


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