Update comment related to NSX connector type

- Comment in parentheses was inteded to tell user which values he can
  use for connector type when it was a text edit field.  Right now NSX
  connector type appears as dropdown list and comment is not usefull any
  longer. Zap it.

Change-Id: Ia42508d3be59ae3ffa541d4c1dad66aa2cff0816