monitor: Break out readline_show_prompt (Jan Kiszka)

Break readline_show_prompt out of readline_start so that (re-)printing
the prompt can be controlled in a more fine-grained way.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6709 c046a42c-6fe2-441c-8c8c-71466251a162