keyboard doesn't always work

[marcusoverhagen]

The keyboard driver is not always opened by the input_server.

The ps2 bus manager does a devfs_publish_device "input/keyboard/at/0" with result B_OK, but input_server does ignore the device sometimes, and then the driver open hook is not called, and it doesn't work.

I added enough debug output to the normal (as in: not compiled as DEBUG=1) ps2 driver to make this visible, search for "keyboard_open" and "mouse_open".