[openib-general][kdapl]: vmalloc instead of kmalloc

[Guy German]

Hi,

There are some places where kmalloc might not be enough :
in dapl_evd_event_alloc there is an allocation:

	event = kmalloc(evd->qlen * sizeof *event);

whereas evd->qlen can be 128k (depends on max_cqe of the hca) 
and kmalloc would fail.

The same goes to dapl_rbuf_alloc.

Is it legit to replace those kmallocs with vmallocs ?

Thanks,
Guy