qemu.tests.netperf_stress: Add netperf_package_sizes parameter to test multi package size.

Signed-off-by: Feng Yang <fyang@redhat.com>
qemu.tests: Add sr_iov_netperf_test test case.

Signed-off-by: Feng Yang <fyang@redhat.com>
qemu.tests: Add device_assignment_netperf_test test case.

Signed-off-by: Feng Yang <fyang@redhat.com>
Merge pull request #145 from FengYang/sr_iov_netperf

Sr iov netperf