ARM: tegra: Enable the DFLL on the Jetson TK1

Add the board-specific properties of the DFLL for the Jetson TK1 board.
On this board, the DFLL will take control of the sd0 regulator on the
on-board AS3722 PMIC.

Signed-off-by: Tuomas Tynkkynen <ttynkkynen@nvidia.com>
Signed-off-by: Mikko Perttunen <mikko.perttunen@kapsi.fi>
Acked-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>