This enables virtio modules on PowerPC* target.
On PowerPC64, drivers are also kernel builtin.
QEMU currently needs to be patched to in order to work on LE hosts due to known issue affecting pre-1.0 (legacy) virtio drivers.
The patch was submitted to QEMU mail list by @afscoelho_gmail.com, available at https://lists.nongnu.org/archive/html/qemu-devel/2020-01/msg01496.html