rockchip: clk: rk3128: fix NANDC_PLL_SEL_MASK

The PLL selector field for NANDC is only 2 bits wide.
This fixes an 'int-overflow on shift' warning.

Fixes: 9246d9e ("rockchip: rk3128: add clock driver")
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/arch/arm/include/asm/arch-rockchip/cru_rk3128.h b/arch/arm/include/asm/arch-rockchip/cru_rk3128.h
index cc317dc..3d8317e 100644
--- a/arch/arm/include/asm/arch-rockchip/cru_rk3128.h
+++ b/arch/arm/include/asm/arch-rockchip/cru_rk3128.h
@@ -136,7 +136,7 @@
 
 	/* CRU_CLK_SEL2_CON */
 	NANDC_PLL_SEL_SHIFT	= 14,
-	NANDC_PLL_SEL_MASK	= 7 << NANDC_PLL_SEL_SHIFT,
+	NANDC_PLL_SEL_MASK	= 3 << NANDC_PLL_SEL_SHIFT,
 	NANDC_PLL_SEL_CPLL	= 0,
 	NANDC_PLL_SEL_GPLL,
 	NANDC_CLK_DIV_SHIFT	= 8,