arm: dts: iot2050: Optionally embed OTP programming data into image

Use external blob otpcmd.bin to replace the 0xff filled OTP programming
command block to create a firmware image that provisions the OTP on
first boot. This otpcmd.bin is generated from the customer keys using
steps described in the meta-iot2050 integration layer for the device.

Based on original patch by Baocheng Su.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
diff --git a/board/siemens/iot2050/Kconfig b/board/siemens/iot2050/Kconfig
index a2b4088..e66b242 100644
--- a/board/siemens/iot2050/Kconfig
+++ b/board/siemens/iot2050/Kconfig
@@ -49,4 +49,11 @@
 	bool "Disable eMMC boot via USER button (Advanced version only)"
 	default y
 
+config IOT2050_EMBED_OTPCMD
+	bool "Embed OTP programming data"
+	help
+	  Embed signed OTP programming data 'otpcmd.bin' into the firmware
+	  image. This data will be evaluated and executed on first boot of the
+	  device.
+
 endif