Remove from start/end dates if tz is not None (#7901, #7835)

Below fixes date_range when input dates are localized.  In that case inferred_freq is not None and so the dates do not have their tzinfo removed.  This causes a fixed offset to be applied when the range is created.  If tzinfo is removed, they will be correctly localized.  

Fixes #7901 
Fixes #7835.