clk: tegra: Use common of_clk_init function

Use common of_clk_init() function for clocks initialization.

Signed-off-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Reviewed-by: Thierry Reding <thierry.reding@gmail.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>