librdmacm: Check that send and recv CQs are different before destroying

librdmacm: Check that send and recv CQs are different before destroying

ucma_destroy_cqs() destroys both the send and recv CQs if they
are non-null.  If the two CQs are actually the same one, this
results in a crash when trying to destroy the second CQ.  Check
that the CQs are different before destroying the second CQ.

This fixes a crash when using rsockets, which sets the send and
recv CQs to the same CQ.

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