Handle the bail out case in the signal path

When a TAP test program asks to bail out, we forcibly kill it.  As a
result, it is very likely that our later wait() will tell us that the
program exited due to a signal... and, because we caused it upon
request of the test, we need to report the test as failed instead of
broken.

However, there is a race.  If the test program happens to finish after
it has printed the "Bail out!" message and before we send the signal,
the program will exit cleanly.  I guess this (different scheduling
behavior) is why the code worked at all in FreeBSD but failed in NetBSD.

tap_main.c

@@ -100,8 +100,14 @@ status_to_result(int status, const kyua_tap_summary_t* summary,
     } else {
         assert(WIFSIGNALED(status));
         *success = false;
-        return kyua_result_write(result_file, KYUA_RESULT_BROKEN,
-                                 "Received signal %d", WTERMSIG(status));
+
+        if (summary->bail_out) {
+            return kyua_result_write(result_file, KYUA_RESULT_FAILED,
+                                     "Bailed out");
+        } else {
+            return kyua_result_write(result_file, KYUA_RESULT_BROKEN,
+                                     "Received signal %d", WTERMSIG(status));
+        }
     }
 }