Added reference counting mechanism for XRC target QPs between
ib_uqp_object and its ib_uxrcd_object.  This prevents closing an XRC
domain that is still attached to a QP.  In addition, add missing code
in ib_uverbs_destroy_srq() to handle ib_uxrcd_object reference
counting correctly when destroying an xsrq.
Signed-off-by: NYishai Hadas <yishaih@mellanox.com>
Signed-off-by: NJack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NRoland Dreier <roland@purestorage.com>