Add target and host platform enumerations so we're not using strings.

Differential Revision: http://reviews.llvm.org/D17088

llvm-svn: 261241
diff --git a/lldb/packages/Python/lldbsuite/test/lldbplatformutil.py b/lldb/packages/Python/lldbsuite/test/lldbplatformutil.py
index efc806c..bf06e18 100644
--- a/lldb/packages/Python/lldbsuite/test/lldbplatformutil.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbplatformutil.py
@@ -4,11 +4,13 @@
 from __future__ import absolute_import
 
 # System modules
+import itertools
 import re
 import subprocess
 import sys
 
 # Third-party modules
+import six
 from six.moves.urllib import parse as urlparse
 
 # LLDB modules