rsocket: Reduce SQ from 2 SGE per WR to 1 SGE

rsocket: Reduce SQ from 2 SGE per WR to 1 SGE

We currently request 2 SGEs per WR when allocating a QP.  The
second SGE is only used when sending data at the end of
the circular send buffer and the start.  All other sends are
restricted to a single SGE.

Reduce the size of the SQ by only requesting 1 SGE per WR.  The
resulting performance is basically unaffected.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>