tty: serial: 8250: Fix whitespace errors

This patch fixes whitespace errors reported by checkpatch to increase
readability. Main focus is on missing spaces after commas in
function headers and macros (like foo,bar edited to foo, bar).

Signed-off-by: Anton Würfel <anton.wuerfel@fau.de>
Signed-off-by: Phillip Raffeck <phillip.raffeck@fau.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-kernel@i4.cs.fau.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>