ARM: tegra: Add clock-cells property to PMC

Tegra PMC has clk_out_1, clk_out_2, clk_out_3, and blink clock.

These clocks were erroneously provided by the clock and reset controller
and are now provided by the PMC instead because that's where the primary
controls are.

This patch adds #clock-cells property with 1 clock specifier to the
Tegra PMC node in device tree.

Tested-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>