BaseTools: Use absolute import in Ecc

Based on "futurize -f libfuturize.fixes.fix_absolute_import

Contributed-under: TianoCore Contribution Agreement 1.1
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>

BaseTools/Source/Python/Ecc/Exception.py

@@ -15,7 +15,8 @@
 # Import Modules
 #
 from __future__ import print_function
-from Xml.XmlRoutines import *
+from __future__ import absolute_import
+from .Xml.XmlRoutines import *
 import Common.LongFilePathOs as os
 
 # ExceptionXml to parse Exception Node of XML file