qemu: initialize hot add system / acpi gpe (Marcelo Tosatti)

ACPI GPE support, used by PCI (and CPU) hotplug.

From: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6607 c046a42c-6fe2-441c-8c8c-71466251a162
