ARM: dts: stm32: keep uart4 behavior on stm32mp157a-iot-box

DMA configuration is added to uart nodes in stm32mp15x device tree.
Delete uart4 DMA property in stm32mp157a-iot-box board device tree to
keep console in irq mode, as DMA support for console has been removed
from the driver by commit e359b441 ("serial: stm32: fix threaded
interrupt handling").
Signed-off-by: NErwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: NAlexandre Torgue <alexandre.torgue@foss.st.com>

arch/arm/boot/dts/stm32mp157a-iot-box.dts

@@ -58,6 +58,8 @@
 	/delete-property/st,hw-flow-ctrl;
 	cts-gpios = <&gpioa 15 GPIO_ACTIVE_LOW>;
 	rts-gpios = <&gpiob 0 GPIO_ACTIVE_LOW>;
+	/delete-property/dmas;
+	/delete-property/dma-names;
 	status = "okay";
 
 	bluetooth {