memory: tegra: Correct debugfs clk rate-range on Tegra30

Correctly set clk rate-range if number of available timings is zero.
This fixes noisy "invalid range [4294967295, 0]" error messages during
boot.

Fixes: 8cee32b4 ("memory: tegra: Implement EMC debugfs interface on Tegra30")
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/memory/tegra/tegra30-emc.c

@@ -1256,6 +1256,11 @@ static void tegra_emc_debugfs_init(struct tegra_emc *emc)
 			emc->debugfs.max_rate = emc->timings[i].rate;
 	}
 
+	if (!emc->num_timings) {
+		emc->debugfs.min_rate = clk_get_rate(emc->clk);
+		emc->debugfs.max_rate = emc->debugfs.min_rate;
+	}
+
 	err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
 				 emc->debugfs.max_rate);
 	if (err < 0) {