qemu with hax to log dma reads & writes jcs.org/2018/11/12/vfio

.shippable.yml: disable powerpc-cross image

Something has happened to the old emdebian setup which means it no
longer builds. Let's disable the shippable builds which are always
failing.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

-2
-2
.shippable.yml
··· 23 23 TARGET_LIST=mips-softmmu,mipsel-linux-user 24 24 - IMAGE=debian-mips64el-cross 25 25 TARGET_LIST=mips64el-softmmu,mips64el-linux-user 26 - - IMAGE=debian-powerpc-cross 27 - TARGET_LIST=ppc-softmmu,ppcemb-softmmu,ppc-linux-user 28 26 - IMAGE=debian-ppc64el-cross 29 27 TARGET_LIST=ppc64-softmmu,ppc64-linux-user,ppc64abi32-linux-user 30 28 build: