Current cxgb4 arm CQ logic ignores IB_CQ_REPORT_MISSED_EVENTS for
request completion notification on a CQ. Due to this ib_poll_handler()
assumes all events polled and avoids further iopoll scheduling.

This patch adds logic to cxgb4 ib_req_notify_cq() handler to check if
CQ is not empty and return accordingly. Based on the return value of
ib_req_notify_cq() handler, ib_poll_handler() will schedule a run of
iopoll handler.
Signed-off-by: NPotnuri Bharat Teja <bharat@chelsio.com>
Reviewed-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>