osc/rdma: fix warnings introduced by r31204

cmr=v1.8:ticket=#4449
osc/base: add support for datatypes that are a contiguous combination
of the primitive datatype

In this case we can not use the convertor to run the accumulate operation
since the datatype is a more or less a primitive type.

cmr=v1.8:ticket=#4449
osc/rdma: quiet warning in r31197

cmr=v1.8:ticket=#4441
osc/rdma: fix possible error when encountering accumulate lock contention

It is possible to get into a situation where a small accumulate operation
can not be completed because a large accumulate operation holds the lock.
In this case we may return from wait/flush/etc before the operation is
complete. To handle this case increment the expected incoming fragment
count when queuing an accumulate operation and increment the incoming
fragment count after processing the accumulate operation.

cmr=v1.8:reviewer=jsquyres
usnic: drop unknown connection checker packets without erroring out

In most cases, bad messages received by the connectivty checker are
just dropped.  However, in one specific code path, a bad packet caused
an abort.  Doh!

This commit does two things:

1. Improve verbose messages for all these cases
1. Simply drop incoming messages that cannot be identified as ACKs or PINGs

Submitted by Jeff Squyres, reviewed by Dave Goodell.

cmr=v1.8:reviewer=ompi-rm1.8