ppc: add IPMI support

OpenPOWER systems use a BT device to communicate with the BMC.
Provide support for it.
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

default-configs/ppc64-softmmu.mak

@@ -6,6 +6,10 @@ include usb.mak
 CONFIG_VIRTIO_VGA=y
 CONFIG_ESCC=y
 CONFIG_M48T59=y
+CONFIG_IPMI=y
+CONFIG_IPMI_LOCAL=y
+CONFIG_IPMI_EXTERN=y
+CONFIG_ISA_IPMI_BT=y
 CONFIG_SERIAL=y
 CONFIG_PARALLEL=y
 CONFIG_I8254=y