tests: Stop test run on NOTE command failure

There is no point trying to go through a test case if the NOTE command
to write TEST-START entry does not succeed. This avoids some excessive
waits on buildbot trying to forcefully kill the programs on its timeout
if wpa_supplicant gets stuck waiting for something (like the current
issue with libnl events and commands having a chance of hitting a
blocking wait on netlink messages).

Signed-hostap: Jouni Malinen <j@w1.fi>

tests/hwsim/run-tests.py

@@ -124,6 +124,8 @@ def main():
             except Exception, e:
                 logger.info("Failed to issue TEST-START before " + t.__name__ + " for " + d.ifname)
                 logger.info(e)
+                print "FAIL " + t.__name__ + " - could not start test"
+                sys.exit(1)
         try:
             if t.func_code.co_argcount > 1:
                 res = t(dev, apdev)