staging: comedi: serial2002: cleanup tty_setspeed()

Rename the two local variables used to set the serial port speed
and latency so thy are unique.

Remove the unnecessary '{ }' around the code and the extra indents.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>