tools/validate_descriptor.py reconverted as python3 script

Change-Id: I6827fc17f79a99668205d74ae297fcfb41c1bb00
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/descriptor-packages/tools/generate_descriptor_pkg.sh b/descriptor-packages/tools/generate_descriptor_pkg.sh
index f54cd2c..1b9a9e0 100755
--- a/descriptor-packages/tools/generate_descriptor_pkg.sh
+++ b/descriptor-packages/tools/generate_descriptor_pkg.sh
@@ -797,7 +797,7 @@
     cd $BASE_DIR
     # Mrityunjay Yadav: Validate descriptor
     GEN_BASEDIR=$(dirname "$0")
-    python $GEN_BASEDIR/validate_descriptor.py $BASE_DIR/$PKG/$descriptor
+    python3 $GEN_BASEDIR/validate_descriptor.py $BASE_DIR/$PKG/$descriptor
     if [ $? -ne 0 ]; then
         rc=$?
         echo "ERROR: validating descriptor for $PKG ($rc)" >&2
diff --git a/descriptor-packages/tools/validate_descriptor.py b/descriptor-packages/tools/validate_descriptor.py
index 3c6dd41..92b61c9 100755
--- a/descriptor-packages/tools/validate_descriptor.py
+++ b/descriptor-packages/tools/validate_descriptor.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python2
+#!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
 ##
@@ -110,7 +110,7 @@
 
         for o, a in opts:
             if o in ("-v", "--version"):
-                print ("test descriptor version THREE " + __version__ + ' ' + version_date)
+                print("test descriptor version THREE " + __version__ + ' ' + version_date)
                 sys.exit()
             elif o in ("-h", "--help"):
                 usage()