Crypto: Align PSA headers entirely to Mbed TLS 3.6.0

This also simplifies the client attributes translation between
client view and service view and reorganized how the Mbed TLS
config files are handled between NS/S (client/service) sides.
At the same time, perform a CMake targets refactoring to allow
exporting a client side view of the config files.

Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
Change-Id: I9a715f9ef40fc223992575ecbac5cf23d162a326
diff --git a/interface/include/mbedtls/README.rst b/interface/include/mbedtls/README.rst
new file mode 100644
index 0000000..9af2e26
--- /dev/null
+++ b/interface/include/mbedtls/README.rst
@@ -0,0 +1,10 @@
+######
+README
+######
+
+The header files contained in this directory are from the
+`Mbed TLS project <https://github.com/Mbed-TLS/mbedtls.git>`_ and they
+retain their own copyright and dual license. The TF-M project uses them
+under the Apache-2.0 license only.
+
+*Copyright (c) The TrustedFirmware-M Contributors. All rights reserved.*