serial: 8250_port: Fix spelling mistake

Change 'timeing' to 'timing'.
Change 'Characteres' to 'Characters'.

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Link: https://lore.kernel.org/r/20220629094411.39066-1-jiaming@nfschina.com


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