mbedtls_ssl_get_handshake_transcript is unusable without hashes

Mark unused variables when compiling without
SHA256 and SHA384. In future a proper dependency
will be added to TLS 1.2 to enforce either of these hashes
to be on.
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index c8904f2..c3bb9f9 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -5261,6 +5261,13 @@
 #endif /* MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA*/
 
     default:
+#if !defined(MBEDTLS_HAS_ALG_SHA_384_VIA_MD_OR_PSA_BASED_ON_USE_PSA) && \
+    !defined(MBEDTLS_HAS_ALG_SHA_256_VIA_MD_OR_PSA_BASED_ON_USE_PSA)
+    (void) ssl;
+    (void) dst;
+    (void) dst_len;
+    (void) olen;
+#endif
         break;
     }
     return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );