VMware: trivial fix for comment

The patch makes a few minor changes to a comment that was added in
commit I7598afbf0dc3c527471af34224003d28e64daaff

TrivialFix

Change-Id: Ic12b0b17aac6f745e62bade37204af516e50df0d
Use six.text_type instead of unicode

According to 6683905b532b6030989064636aa5506d4cbe5b22 ,
we shouldn't use unicode in an exception message.

Change-Id: I377f0cf7b8a66026491b75e89b470a328670f17a
Merge "VMware: trivial fix for comment"
Merge "Use six.text_type instead of unicode"