The syscons code disabled scroll lock inside sc_cnputs() if it's going
to print a system message. The code currently wants to process any TTY
output data as well, but we cannot do this, because the TTY lock is a
sleep mutex, while cnputs() picks up a spin mutex.
Disable the code for now. It solves a panic when a console message is
printed while scroll lock is enabled. One solution would be to
initialize a task structure here.
Reported by: Paul B. Mahol <onemda gmail com>