tegra: Correct PLL access in ap20.c and clock.c

Correct this warning seen by Albert:

ap20.c:44:18: warning: array subscript is above array bounds

There is a subtle bug here which currently causes no errors, but might
in future if people use PCI or the 32KHz clock. So take the opportunity
to correct the logic now.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/cpu/armv7/tegra2/ap20.c b/arch/arm/cpu/armv7/tegra2/ap20.c
index 698bfd0..24e582d 100644
--- a/arch/arm/cpu/armv7/tegra2/ap20.c
+++ b/arch/arm/cpu/armv7/tegra2/ap20.c
@@ -77,8 +77,10 @@
 
 void init_pllx(void)
 {
-	struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
-	struct clk_pll *pll = &clkrst->crc_pll[CLOCK_ID_XCPU];
+	struct clk_rst_ctlr *clkrst =
+			(struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+	struct clk_pll_simple *pll =
+		&clkrst->crc_pll_simple[CLOCK_ID_XCPU - CLOCK_ID_FIRST_SIMPLE];
 	u32 reg;
 
 	/* If PLLX is already enabled, just return */