If reboot was called from inside the Xserver there could happen a race
condition where chvt would never end, and therefore the whole system was
stalled.
The user could not recover the system by ssh the machine or using the
keyboard.
Running chvt in background fixes the issue.
Also move sleep 1s inside stop to give time for killproc xinit for
fix issue when chvt 1 don't work because X server is still running.
