bitbake: toaster: use items and range instead of old APIs

Used items() and range() APIs instead of iteritems() and
xrange() as latter don't exist in python 3

[YOCTO #9584]

(Bitbake rev: 372dd3abcb201bd9ac2c3189c5505d3578ce0dd0)

Signed-off-by: Ed Bartosh <ed.bartosh@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/toaster/orm/models.py

@@ -103,7 +103,7 @@ class GitURLValidator(validators.URLValidator):
 
 def GitURLField(**kwargs):
     r = models.URLField(**kwargs)
-    for i in xrange(len(r.validators)):
+    for i in range(len(r.validators)):
         if isinstance(r.validators[i], validators.URLValidator):
             r.validators[i] = GitURLValidator()
     return r