tests.cfg.netperf.cfg : Make test support different types of network adapters

Remove the limit of virtio_net, make the test support different types of
network adapters like e1000 and rtl8139

Signed-off-by: Yunping Zheng <yunzheng@redhat.com>
qemu_cpu.cfg: Remove PCLMULQDQ bug from whitelist

The pclmulqdq bug is fixed on qemu.git on commit
56383703c060777fd01aaf8d63d5f46d660e9fb9, so we can stop ignoring the
bug and report as an actual failure.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
qemu_cpu.cfg: Whitelist known (but harmless) RHEL6 SVM CPUID bug

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Merge pull request #741 from humanux/netperf

 tests.cfg.netperf.cfg : Make test support different types of network apapters
qemu.tests: small bug fix in nmi_bsod_catch

Give a default value "" to reboot_after_config. Otherwise it will raise
an TypeError(argument of type 'NoneType' is not iterable) when it is None.

Signed-off-by: Yiqiao Pu <ypu@redhat.com>