MFC r361715:

[psm] Do not disable trackpoint when hw.psm.elantech.touchpad_off is enabled

PR: 246117
Reported by: Alexander Sieg <ports@xanderio.de>

MFC r361718:

[psm] Workaround active PS/2 multiplexor hang

which happens on some laptops after returning to legacy multiplexing mode
at initialization stage.

PR: 242542
Reported by: Felix Palmen <felix@palmen-it.de>