classes/lib: Complete transition to python3

This patch contains all the other misc pieces of the transition to
python3 which didn't make sense to be broken into individual patches.

(From OE-Core rev: fcd6b38bab8517d83e1ed48eef1bca9a9a190f57)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/lib/oeqa/utils/dump.py

@@ -3,7 +3,7 @@ import sys
 import errno
 import datetime
 import itertools
-from commands import runCmd
+from .commands import runCmd
 
 def get_host_dumper(d):
     cmds = d.getVar("testimage_dump_host", True)