dt-bindings: nvmem: stm32: new property for data access

Introduce boolean property st,non-secure-otp for OTP data located
in a factory programmed area that only secure firmware can access
by default and that shall be reachable from the non-secure world.

This change also allows additional properties for NVMEM nodes that
were forbidden prior this change.
Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Documentation/devicetree/bindings/nvmem/nvmem.yaml

@@ -67,8 +67,6 @@ patternProperties:
     required:
       - reg
 
-    additionalProperties: false
-
 examples:
   - |
       #include <dt-bindings/gpio/gpio.h>

Documentation/devicetree/bindings/nvmem/st,stm32-romem.yaml

@@ -24,6 +24,18 @@ properties:
       - st,stm32f4-otp
       - st,stm32mp15-bsec
 
+patternProperties:
+  "^.*@[0-9a-f]+$":
+    type: object
+
+    properties:
+      st,non-secure-otp:
+        description: |
+          This property explicits a factory programmed area that both secure
+          and non-secure worlds can access. It is needed when, by default, the
+          related area can only be reached by the secure world.
+        type: boolean
+
 required:
   - "#address-cells"
   - "#size-cells"
@@ -41,6 +53,11 @@ examples:
       calib@22c {
         reg = <0x22c 0x2>;
       };
+
+      mac_addr@e4 {
+        reg = <0xe4 0x8>;
+        st,non-secure-otp;
+      };
     };
 
 ...