nrf_security: Don't use PSA dynamic key store Kconfig

This makes sure that the MBEDTLS_PSA_KEY_STORE_DYNAMIC is never
forwarded to the build.
It also makes the help text more descriptive.

Signed-off-by: Georgios Vasilakis <georgios.vasilakis@nordicsemi.no>

Author: Vge0rge

subsys/nrf_security/Kconfig.psa

@@ -82,6 +82,11 @@ config MBEDTLS_PSA_KEY_STORE_DYNAMIC
 	  This option is incompatible with nrf_security when builtin keys are being used.
 	  Since the builtin keys are considered an integral part of nrf_security this option
 	  should not be enabled.
+	  This option is not forwarded to the header files of nrf_security and it is kept
+	  here only for visibility. The PSA key store design defines the hydrid key store
+	  implicitely when both this option and the option regarding the static key slots
+	  are disabled so it is valuable in the build to see that this is disabled.
+
 
 config MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE
 	int "PSA static key slot buffer size in bytes"

subsys/nrf_security/cmake/psa_crypto_config.cmake

@@ -465,7 +465,6 @@ kconfig_check_and_set_base_to_one(MBEDTLS_PSA_CRYPTO_DRIVERS)
 kconfig_check_and_set_base_int(MBEDTLS_PSA_KEY_SLOT_COUNT)
 kconfig_check_and_set_base_to_one(MBEDTLS_PSA_STATIC_KEY_SLOTS)
 kconfig_check_and_set_base_int(MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE)
-kconfig_check_and_set_base_to_one(MBEDTLS_PSA_KEY_STORE_DYNAMIC)
 
 # Generate the PSA config file (default nrf-psa-crypto-config.h)
 configure_file(${NRF_SECURITY_ROOT}/configs/psa_crypto_config.h.template

subsys/nrf_security/configs/psa_crypto_config.h.template

@@ -460,7 +460,6 @@
 #cmakedefine MBEDTLS_PSA_KEY_SLOT_COUNT                         @MBEDTLS_PSA_KEY_SLOT_COUNT@
 #cmakedefine MBEDTLS_PSA_STATIC_KEY_SLOTS                       @MBEDTLS_PSA_STATIC_KEY_SLOTS@
 #cmakedefine MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE            @MBEDTLS_PSA_STATIC_KEY_SLOT_BUFFER_SIZE@
-#cmakedefine MBEDTLS_PSA_KEY_STORE_DYNAMIC                      @MBEDTLS_PSA_KEY_STORE_DYNAMIC@
 
 #include <oberon_check_unsupported.h>