[IPMBD] ipmbSend handling

[Tanous, Ed]

> 
> The direction is always from the master device to the slave device.
> 
Not true in either the spec or the implementation.  The IPMB bridge was designed to operate two ways.  First, requests could be made from external entities, like an IPMB header on the board, or the Management Engine (On x86 platforms).  These requests first require the BMC to be a slave for the request, and a master for the response.  Second, the BMC could initiate a request (Probably to the management engine).  In that case, it would be an master for the request, then a slave for the response.  In theory, both scenarios are supported by the daemon, but only the first case might be enabled at this point.

> 
> It seems to me that ipmbSend behavior doesn't get aligned with the description of request/response protocol in IPMB spec.
> 

What do you refer to as ipmbSend here?

It would help a lot if you could add your comments to the code in the gerrit review.  It might help track down where you think the issues are.

-Ed