Minor refactoring of generic SSL certificate verif

Rename as there was a name collision with a static function in another
file: ssl_parse_certificate_verify in ssl_tls12_server.c is the function
that parses the CertificateVerify message, which seems appropriate. Here
it meant "the 'verify' step after parsing the Certificate message".
Use a name that focuses on what it does: verify, not parse.

Also, take ciphersuite_info as an argument: when TLS 1.3 calls this
function, it can pass NULL as the ciphersuite has no influence there.

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index a7c6cac..ad8f3f0 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -7939,14 +7939,13 @@
 }
 
 MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_parse_certificate_verify(mbedtls_ssl_context *ssl,
-                                        int authmode,
-                                        mbedtls_x509_crt *chain,
-                                        void *rs_ctx)
+static int ssl_verify_certificate(mbedtls_ssl_context *ssl,
+                                  int authmode,
+                                  mbedtls_x509_crt *chain,
+                                  const mbedtls_ssl_ciphersuite_t *ciphersuite_info,
+                                  void *rs_ctx)
 {
     int ret = 0;
-    const mbedtls_ssl_ciphersuite_t *ciphersuite_info =
-        ssl->handshake->ciphersuite_info;
     int have_ca_chain_or_callback = 0;
 
     if (authmode == MBEDTLS_SSL_VERIFY_NONE) {
@@ -8246,8 +8245,8 @@
     }
 #endif
 
-    ret = ssl_parse_certificate_verify(ssl, authmode,
-                                       chain, rs_ctx);
+    ret = ssl_verify_certificate(ssl, authmode, chain,
+                                 ssl->handshake->ciphersuite_info, rs_ctx);
     if (ret != 0) {
         goto exit;
     }