ARM: dts: stm32: use RCC macro for CRC node on stm32f746

The patch replaces the number 12 with the appropriate numerical constant
already defined in the file stm32f7-rcc.h.
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

arch/arm/boot/dts/stm32f746.dtsi

@@ -515,7 +515,7 @@ pwrcfg: power-config@40007000 {
 		crc: crc@40023000 {
 			compatible = "st,stm32f7-crc";
 			reg = <0x40023000 0x400>;
-			clocks = <&rcc 0 12>;
+			clocks = <&rcc 0 STM32F7_AHB1_CLOCK(CRC)>;
 			status = "disabled";
 		};