releasetools: Replace iteritems with items.

While in theory this could incur memory overhead for Python 2, the
impact is low for the existing use cases (plus we're moving away from
Python 2).

Bug: 131631303
Test: No additional occurrence of iteritems.
Test: Build with Python 3.
Change-Id: I0205c9edf25f46e3d85967c7dd2c1af035757741
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index 9998cd3..0030afa 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -1460,7 +1460,7 @@
     values.
     """
     result = {}
-    for k, v in sorted(current.iteritems()):
+    for k, v in sorted(current.items()):
       if v:
         result[k] = v
       else:
@@ -1481,7 +1481,7 @@
     f.write("# (Additional spaces are harmless.)\n\n")
 
     first_line = None
-    sorted_list = sorted([(not v, k, v) for (k, v) in current.iteritems()])
+    sorted_list = sorted([(not v, k, v) for (k, v) in current.items()])
     for i, (_, k, v) in enumerate(sorted_list):
       f.write("[[[  %s  ]]] %s\n" % (v, k))
       if not v and first_line is None:
@@ -1647,7 +1647,7 @@
     """Keyword arguments to the constructor become attributes of this
     object, which is passed to all functions in the device-specific
     module."""
-    for k, v in kwargs.iteritems():
+    for k, v in kwargs.items():
       setattr(self, k, v)
     self.extras = OPTIONS.extras