(MFC of r272416)
Add new functions to manipulate these mode & state, instead of calling
kbdd_ioctl() everyhere.
This fixes at least two bugs:
1. The state of the Scroll Lock LED and the state of scroll mode
could be out-of-sync. For instance, if one enables scroll mode on
window #1 and switches to window #2, the LED would remain on, but
the window wouldn't be in scroll mode.
Similarily, when switching between a console and an X.Org
session, the LED states could be inconsistent with the real
state.
2. When exiting from an X.Org session, the user could be unable to
type anything. The workaround was to switch to another console
window and come back.
Differential Revision: https://reviews.freebsd.org/D821
Reviewed by: ray@
Approved by: ray@
Tested by: kwm@
6981999a42