virttest: Update khugepaged test timeout

As the khugepaged process will quit slowly in some OS, enlarge the
timeout for khugepaged test from 5s to 50s. And also use the method that
check process status in a while loop which will break when the khugepaged
process status is changed as expect instead of time.sleep(timeout).

Signed-off-by: Yiqiao Pu <ypu@redhat.com>
netperf: fix a typo

We compute rpkt_per_exit by tx_pkts, and compute tpkt_per_exit
by rx_pkts. It's wrong.

Signed-off-by: Amos Kong <akong@redhat.com>
Merge pull request #1079 from kongove/for-lmr

Fix a typo in netperf result
virttest.libvirt_xml.pool_xml: Fix py 2.4 incompatible construct

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Merge pull request #1068 from ypu/thp

virttest: Update khugepaged test timeout