ARM: dts: stm32: add initial support for stm32mp157-ultra-fly-sbc board

Add support for Ultratronik's stm32mp157c fly board. This board embeds
a STM32MP157c SOC and 1GB of DDR3. Several connections are available on
this boards: 2*USB2.0, 1*USB2.0 MiniUSB, Debug UART, 1*UART, 1*USART,
SDcard, RJ45, ...

This patch enables basic support for a kernel boot - SD-card or eMMC.

Signed-off-by: Goran Rađenović <goran.radni@gmail.com>
Link: https://lore.kernel.org/r/20250508143818.2574558-5-goran.radni@gmail.com
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>

Author: Goran Rađenović

arch/arm/boot/dts/st/Makefile

@@ -71,7 +71,8 @@ dtb-$(CONFIG_ARCH_STM32) += \
 	stm32mp157c-lxa-tac-gen2.dtb \
 	stm32mp157c-odyssey.dtb \
 	stm32mp157c-osd32mp1-red.dtb \
-	stm32mp157c-phycore-stm32mp1-3.dtb
+	stm32mp157c-phycore-stm32mp1-3.dtb \
+	stm32mp157c-ultra-fly-sbc.dtb
 dtb-$(CONFIG_ARCH_U8500) += \
 	ste-snowball.dtb \
 	ste-hrefprev60-stuib.dtb \