ssl_tls: rename sha_512_psa to sha_384_psa

diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 58f9e36..d9f9802 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -382,7 +382,7 @@
 #endif
 #if defined(MBEDTLS_SHA512_C)
 #if defined(MBEDTLS_USE_PSA_CRYPTO)
-    psa_hash_operation_t fin_sha512_psa;
+    psa_hash_operation_t fin_sha384_psa;
 #else
     mbedtls_sha512_context fin_sha512;
 #endif