opal-ci: Build qemu from Cedric's powernv-2.12 branch

This contains the latest features. It's close to upstream, but there's
enough stuff in there that it probably makes sense to continue using it
for now.

Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Stewart Smith <stewart@linux.ibm.com>

opal-ci/build-qemu-powernv.sh

@@ -2,7 +2,7 @@
 set -e
 set -vx
 
-git clone --depth=1 -b qemu-powernv-for-skiboot-3 git://github.com/open-power/qemu.git
+git clone --depth=1 -b powernv-2.12 git://github.com/legoater/qemu.git
 cd qemu
 git submodule update --init dtc
 export CC="ccache gcc"