net/virtio: use any layout for version 1.0

net/virtio: use any layout for version 1.0

Current virtio driver advertises VERSION_1 support,
but does not handle device's VERSION_1 support when
sending packets (it looks for ANY_LAYOUT feature,
which is absent).

This patch enables 'can_push' in tx path when VERSION_1
is advertised by the device.

This significantly improves small packets forwarding rate
towards devices advertising VERSION_1 feature.

Signed-off-by: Pierre Pfister <ppfister@cisco.com>
Acked-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>