Unbreak mouse on resume on Thinkpads when hw.psm.trackpoint_support=0,
which is default. It was broken in r281441.

It appears that set_trackpoint_parameters() call on resume disables the
mouse. So, we need not call it on resume if hw.psm.trackpoint_support=0.

The problem is that the probe functions are used both for probing and
for reiniting on resume. And the absense of the softc parameter is used
as a mark to distinguish reinit and probe, which is quite ugly. At the
same time the softc parameter is needed to call set_trackpoint_parameters().

o Change the arguments of probefunc_t to always supply the softc, and

use additional enum argument to tell probing from initing.

o Don't call set_trackpoint_parameters() from global doinitialize(),

instead call it from the enable_trackpoint() only.

o In enable_synaptics() call enable_trackpoint() in both probe and

reinit cases.

Together with: Jan Kokemüller <jan.kokemueller gmail.com>