feat(stm32mp1-fdts): add CoT and fuse references for authentication

Add the stm32mp1 CoT description file. Include the TRUSTED_BOARD_BOOT
entry in the platform device tree file.
Add the missing public root key reference for stm32mp15 and the
encryption key reference for stm32mp13.

Change-Id: I0ae2454979a3df6dd3e4361510317742e8fbc109
Signed-off-by: Lionel Debieve <lionel.debieve@foss.st.com>
diff --git a/fdts/stm32mp151.dtsi b/fdts/stm32mp151.dtsi
index bb16fda..a938edc 100644
--- a/fdts/stm32mp151.dtsi
+++ b/fdts/stm32mp151.dtsi
@@ -487,6 +487,9 @@
 			ts_cal2: calib@5e {
 				reg = <0x5e 0x2>;
 			};
+			pkh_otp: pkh_otp@60 {
+				reg = <0x60 0x20>;
+			};
 			mac_addr: mac_addr@e4 {
 				reg = <0xe4 0x8>;
 				st,non-secure-otp;