[nrf noup] modules: mbedtls: do not always enable entropy on MBEDTLS_PSA_CRYPTO_C

This is actually a fromlist of upstream PR # 108256 but the cherry-pick
conflicts too badly.

This will be reverted and cherry-picked properly from upstream in the
Mbed TLS update PR.

Signed-off-by: Tomi Fontanilles <tomi.fontanilles@nordicsemi.no>

Author: tomi-font

modules/mbedtls/Kconfig.tf-psa-crypto

@@ -412,7 +412,8 @@ config MBEDTLS_PKCS5_C
 choice MBEDTLS_PSA_CRYPTO_RNG_SOURCE
 	prompt "PSA crypto random source"
 	depends on MBEDTLS_PSA_CRYPTO_C
-	default MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG if CSPRNG_ENABLED
+	default MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG if CSPRNG_ENABLED \
+						   || !PSA_CRYPTO_PROVIDER_MBEDTLS
 	default MBEDTLS_PSA_CRYPTO_LEGACY_RNG
 
 config MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG
@@ -467,7 +468,7 @@ config MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG_ALLOW_NON_CSPRNG
 config MBEDTLS_PSA_CRYPTO_C
 	bool "Platform Security Architecture cryptography API"
 	depends on !BUILD_WITH_TFM
-	select CSPRNG_NEEDED
+	select CSPRNG_NEEDED if PSA_CRYPTO_PROVIDER_MBEDTLS
 
 config MBEDTLS_USE_PSA_CRYPTO
 	bool "Use PSA APIs instead of legacy MbedTLS when possible"