stm32f429: lcd-dma: Fix LCD clock shift

RCC_DCKCFGR was missing a shift for register write

Author: jkent

examples/stm32/f4/stm32f429i-discovery/lcd-dma/lcd-dma.c

@@ -164,7 +164,7 @@ static void lcd_dma_init(void)
 	RCC_PLLSAICFGR = (sain << RCC_PLLSAICFGR_PLLSAIN_SHIFT |
 			  saiq << RCC_PLLSAICFGR_PLLSAIQ_SHIFT |
 			  sair << RCC_PLLSAICFGR_PLLSAIR_SHIFT);
-	RCC_DCKCFGR |= RCC_DCKCFGR_PLLSAIDIVR_DIVR_8;
+	RCC_DCKCFGR |= RCC_DCKCFGR_PLLSAIDIVR_DIVR_8 << RCC_DCKCFGR_PLLSAIDIVR_SHIFT;
 	RCC_CR |= RCC_CR_PLLSAION;
 	while ((RCC_CR & RCC_CR_PLLSAIRDY) == 0) {
 		continue;