Set focus to monitor to ask password if line is	multiplexed (Laurent Vivier)

This patch allows to display the "Password:" prompt if we use encrypted
disk with "-nographic" option.

It also modifies management of "-nographic" to not override user's
choices for "-serial", "-parallel" and "-monitor".

When qemu has to ask a password with "-nographic" with a multiplexed
serial interface, it forces the focus to the monitor and restore
original focus after.

Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4979 c046a42c-6fe2-441c-8c8c-71466251a162
