Adds support for input event interface in sysmouse(4) driver. Both vt and syscons sysmouses are supported.
For horizontal (T-axis) wheel reporting which is not standardized through existing mouse drivers kern.evdev.sysmouse_t_axis sysctl is introduced. It can take following values:
0 - no T-axis events (default)
1 - T-axis events are originated in ums(4) driver.
2 - T-axis events are originated in psm(4) driver.