clk: tegra: Fix Tegra PMC clock out parents

Tegra PMC clocks clk_out_1, clk_out_2, and clk_out_3 supported parents
are osc, osc_div2, osc_div4 and extern clock.

Clock driver is using incorrect parents clk_m, clk_m_div2, clk_m_div4
for PMC clocks.

This patch fixes this.

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>