[PATCH] linux: Prefer ioctl(KDSKBMUTE, 1) over ioctl(KDSKBMODE, K_OFF)

[Arthur Taylor]

Setting the KDSKBMODE on a VT which X is running is never a good idea.
This is an issue that needs resolution in systemd.

The thought behind reusing KDSKBMODE for disabling keyboard input is
that it doesn't break xf86-input-kbd and SysRq-R still functions.

-Art