Input: psmouse - add module parameters to control OLPC touchpad delays

The HPGK touchpad that is found on the XO driver has historically
exhibitted eratic behaviour in various environments (very dry,
very humid, etc) that can be worked around via some delays. This
patch turns those delays into module parameters to make testing
simpler.

Signed-off-by: Paul Fox <pgf@laptop.org>
Signed-off-by: Deepak Saxena <dsaxena@laptop.org>
Acked-By: Andres Salomon <dilinger@debian.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>