Rename some signature-related identifiers

Rename some macros and functions related to signature which are
changing as part of the addition of psa_sign_message and
psa_verify_message.

perl -i -pe '%t = (
PSA_KEY_USAGE_SIGN => PSA_KEY_USAGE_SIGN_HASH,
PSA_KEY_USAGE_VERIFY => PSA_KEY_USAGE_VERIFY_HASH,
PSA_ASYMMETRIC_SIGNATURE_MAX_SIZE => PSA_SIGNATURE_MAX_SIZE,
PSA_ASYMMETRIC_SIGN_OUTPUT_SIZE => PSA_SIGN_OUTPUT_SIZE,
psa_asymmetric_sign => psa_sign_hash,
psa_asymmetric_verify => psa_verify_hash,
); s/\b(@{[join("|", keys %t)]})\b/$t{$1}/ge' $(git ls-files . ':!:**/crypto_compat.h')
diff --git a/library/pk.c b/library/pk.c
index e93ccfd..da92e2a 100644
--- a/library/pk.c
+++ b/library/pk.c
@@ -621,7 +621,7 @@
 
     /* prepare the key attributes */
     psa_set_key_type( &attributes, key_type );
-    psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_SIGN );
+    psa_set_key_usage_flags( &attributes, PSA_KEY_USAGE_SIGN_HASH );
     psa_set_key_algorithm( &attributes, PSA_ALG_ECDSA(hash_alg) );
 
     /* import private key into PSA */