tests/bgpd: don't hardcode error number (fix f57000c)

f57000c ("bgpd: don't send NOTIFY twice for malformed attrs") introduces
BGP_ATTR_PARSE_ERROR_NOTIFYPLS as additional error code that implies the
caller should sent a NOTIFY and convert it to BGP_ATTR_PARSE_ERROR.
Sadly, the latter was hardcoded in bgp_mp_attr_test.c, which now didn't
consider the new value to be an error.

Make the testcase treat all nonzero values as error without discern.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/tests/bgp_mp_attr_test.c b/tests/bgp_mp_attr_test.c
index 177c1ad..aa8e485 100644
--- a/tests/bgp_mp_attr_test.c
+++ b/tests/bgp_mp_attr_test.c
@@ -478,7 +478,7 @@
   
   printf ("parsed?: %s\n", ret ? "no" : "yes");
   
-  if (ret != t->parses)
+  if ((ret == 0) != (t->parses == 0))
     failed++;
   
   if (tty)