clk: tegra: Init cfg structure in _get_pll_mnp

Not all fields are read from the hw depending on the PLL type. Make sure
the other fields are 0 by clearing the structure beforehand to prevent
users such as the rate re-calculation code from using bogus values.

Based on work by  Alex Frid <afrid@nvidia.com>

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/tegra/clk-pll.c

@@ -690,6 +690,8 @@ static void _get_pll_mnp(struct tegra_clk_pll *pll,
 	struct tegra_clk_pll_params *params = pll->params;
 	struct div_nmp *div_nmp = params->div_nmp;
 
+	*cfg = (struct tegra_clk_pll_freq_table) { };
+
 	if ((params->flags & (TEGRA_PLLM | TEGRA_PLLMB)) &&
 		(pll_override_readl(PMC_PLLP_WB0_OVERRIDE, pll) &
 			PMC_PLLP_WB0_OVERRIDE_PLLM_OVERRIDE)) {