feat(stm32mp15-fdts): add support for prtt1x board family

Add one device tree to support a family of boards (PRTT1C, PRTT1S,
PRTT1A) based on STM32MP151AAD3, used as sensors and actuators for
industrial, 10BaseT1L based networks.

This change was tested with barebox 2022.12.0 bootloader and kernel
v6.2.0-rc1.

Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Change-Id: Ibab9933eadd7aa379ae0a7c7ccbfc2fbb9a44ca8
3 files changed