avocado.utils.pci: Fix the absolute import

The genio import is suppose to be relative one.
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

avocado/utils/pci.py

@@ -23,7 +23,7 @@ Module for all PCI devices related functions.
 
 import re
 import os
-from genio import read_file
+from .genio import read_file
 from . import process