Enable MBEDTLS_PSA_CRYPTO_CONFIG in "config.py full"

Back when we introduced MBEDTLS_PSA_CRYPTO_CONFIG and it was still
experimental, it made sense that we tested it separately. Nowadays, the
feature is fully implemented, and the full config without
MBEDTLS_PSA_CRYPTO_CONFIG keeps cryptographic mechanisms that only have a
PSA implementation and aren't in the default build disabled (currently:
PBKDF2). So enable MBEDTLS_PSA_CRYPTO_CONFIG in the full config.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/scripts/config.py b/scripts/config.py
index 3e957fd..5810a4a 100755
--- a/scripts/config.py
+++ b/scripts/config.py
@@ -205,7 +205,6 @@
     'MBEDTLS_NO_PLATFORM_ENTROPY', # removes a feature
     'MBEDTLS_NO_UDBL_DIVISION', # influences anything that uses bignum
     'MBEDTLS_PLATFORM_NO_STD_FUNCTIONS', # removes a feature
-    'MBEDTLS_PSA_CRYPTO_CONFIG', # toggles old/new style PSA config
     'MBEDTLS_PSA_CRYPTO_EXTERNAL_RNG', # behavior change + build dependency
     'MBEDTLS_PSA_CRYPTO_KEY_ID_ENCODES_OWNER', # incompatible with USE_PSA_CRYPTO
     'MBEDTLS_PSA_CRYPTO_SPM', # platform dependency (PSA SPM)