mq_open return status is set as ERROR

[TaiJuWu]

Summary

mq_open return status is set as ERROR instead of -1

Impact

None

Testing

Noe

[pkarashchenko]

I do not see any benefit of this change. From application point of view (mqd_t)-1 is more portable

[TaiJuWu]

In my mind, error is more intuitive than -1.
If it's not good idea, I will close this PR.
Thank you.

[pkarashchenko]

From POSIX perspective the ERROR is not defined, so from Linux/FreeBSD/OSX/NuttX portability point of view the -1 is better.
I think we can use ERROR in kernel code, but -1 in application if we are talking about POSIX API that define -1 as return value

[TaiJuWu]

@pkarashchenko Thank you for your reply.