[nrf fromlist] secure_storage: Forbit usage with NRF_IRONSIDE

The NRF_IRONSIDE is a provider of PSA services (including storage)
so it cannot be used along with the secure storage subsystem which
provides PSA storage APIs.

Upstream PR: 96915

Signed-off-by: Georgios Vasilakis <[email protected]>

Author: Vge0rge

subsys/secure_storage/Kconfig

@@ -4,6 +4,7 @@
 menuconfig SECURE_STORAGE
 	bool "Secure storage subsystem"
 	depends on !BUILD_WITH_TFM
+	depends on !NRF_IRONSIDE
 	select MBEDTLS_PSA_CRYPTO_STORAGE_C if MBEDTLS_PSA_CRYPTO_C
 	select EXPERIMENTAL
 	help