ui: avoid 'local_err' variable shadowing in VNC SASL auth

The start_auth_sasl() method declares a 'Error *local_err' variable in
an inner if () {...} scope, which shadows a variable of the same name
declared at the start of the method. This is confusing for reviewers and
may trigger compiler warnings.

Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20180205114938.15784-3-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

ui/vnc-auth-sasl.c

@@ -556,7 +556,6 @@ void start_auth_sasl(VncState *vs)
     /* Inform SASL that we've got an external SSF layer from TLS/x509 */
     if (vs->auth == VNC_AUTH_VENCRYPT &&
         vs->subauth == VNC_AUTH_VENCRYPT_X509SASL) {
-        Error *local_err = NULL;
         int keysize;
         sasl_ssf_t ssf;
 
@@ -565,7 +564,6 @@ void start_auth_sasl(VncState *vs)
         if (keysize < 0) {
             trace_vnc_auth_fail(vs, vs->auth, "cannot TLS get cipher size",
                                 error_get_pretty(local_err));
-            error_free(local_err);
             sasl_dispose(&vs->sasl.conn);
             vs->sasl.conn = NULL;
             goto authabort;