ARM: tegra: Implement tegra_plle_enable()

This function is required by PCIe and SATA. This patch implements it on
Tegra20, Tegra30 and Tegra124. It isn't implemented for Tegra114 because
it doesn't support PCIe or SATA.

Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/include/asm/arch-tegra20/clock.h b/arch/arm/include/asm/arch-tegra20/clock.h
index 889c65a..4df8da9 100644
--- a/arch/arm/include/asm/arch-tegra20/clock.h
+++ b/arch/arm/include/asm/arch-tegra20/clock.h
@@ -15,4 +15,6 @@
 #define OSC_FREQ_SHIFT          30
 #define OSC_FREQ_MASK           (3U << OSC_FREQ_SHIFT)
 
+int tegra_plle_enable(void);
+
 #endif	/* _TEGRA20_CLOCK_H */