tty: 8250, remove shadow and unused variables

The compiler complains about variables that are set, but never used:
* intX variables in exar_handle_irq
  drivers/tty/serial/8250/8250_port.c:1864:34: warning: variable ‘int3’ set but not used [-Wunused-but-set-variable]
* val variable in pci_quatech_wqopr
  drivers/tty/serial/8250/8250_pci.c:1139:10: warning: variable ‘val’ set but not used [-Wunused-but-set-variable]

And about a shadow variable:
* tmout in wait_for_xmitr is defined twice with the same type. Both of
  them are also initialized before use.

Remove all of them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Matt Schulte <matts@commtech-fastcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>