arm: tegra: tn8 quick charge 2 board support

arm: tegra: tn8 quick charge 2 board support

Add changes to board file to support QC2 TN8
quick charge capable is only set for E1936 PMU

add note describing how to configure current
and voltage in the board file.

Bug 1424733

Change-Id: Ibf40d3be8f81a3228c6446475ec44963c986ddc0
Reviewed-on: http://git-master/r/355973
(cherry picked from commit 9524afb32129617f5320504090bad6a69c95d884)
Signed-off-by: Philip Rakity <prakity@nvidia.com>
Reviewed-on: http://git-master/r/363213
Reviewed-by: Juha Tukkinen <jtukkinen@nvidia.com>
Tested-by: Juha Tukkinen <jtukkinen@nvidia.com>