No, dehaze feature is not available in Lightroom 6 standalone.
It is available only in CC version.
None of the new features added to CC after the initial release are not, and will not ever be available in LR6.
They will be available in LR7, if Adobe continues to offer standalone versions of LR.
thanks very much - my query has been answered - question is whether LR7 will be offered as an upgrade to LR5
When (and if) LR7 is released, I would have thought that upgrades from previous versions will be offered. (although nobody can tell for certain)
You can upgrade to LR6 from any previous version, even version 1.
As for Dehaze, there are some options available for LR6.
Do a google search for "free dehaze" or similar.