tools/kvm_stat: eliminate extra guest/pid selection dialog

tools/kvm_stat: eliminate extra guest/pid selection dialog

BugLink: http://bugs.launchpad.net/bugs/1734130
We can do with a single dialog that takes both, pids and guest names.
Note that we keep both interactive commands, 'p' and 'g' for now, to
avoid confusion among users used to a specific key.

While at it, we improve on some minor glitches regarding curses usage,
e.g. cursor still visible when not supposed to be.

Signed-off-by: Stefan Raspl <raspl@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 516f1190a1e0cce12128a6446e6438745c8de62a)
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>