RDMA/cma: Fix kmemleak in rdma_core observed during blktests nvme/rdma use siw

In the Linux kernel, the following vulnerability has been resolved:

RDMA/cma: Fix kmemleak in rdma_core observed during blktests nvme/rdma use siw

When running blktests nvme/rdma, the following kmemleak issue will appear.

kmemleak: Kernel memory leak detector initialized (mempool available:36041)
kmemleak: Automatic memory scanning thread started
kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 8 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 17 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 4 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

unreferenced object 0xffff88855da53400 (size 192):
comm "rdma", pid 10630, jiffies 4296575922
hex dump (first 32 bytes):
37 00 00 00 00 00 00 00 c0 ff ff ff 1f 00 00 00 7...............
10 34 a5 5d 85 88 ff ff 10 34 a5 5d 85 88 ff ff .4.].....4.]....
backtrace (crc 47f66721):
[<ffffffff911251bd>] kmalloc_trace+0x30d/0x3b0
[<ffffffffc2640ff7>] alloc_gid_entry+0x47/0x380 [ib_core]
[<ffffffffc2642206>] add_modify_gid+0x166/0x930 [ib_core]
[<ffffffffc2643468>] ib_cache_update.part.0+0x6d8/0x910 [ib_core]
[<ffffffffc2644e1a>] ib_cache_setup_one+0x24a/0x350 [ib_core]
[<ffffffffc263949e>] ib_register_device+0x9e/0x3a0 [ib_core]
[<ffffffffc2a3d389>] 0xffffffffc2a3d389
[<ffffffffc2688cd8>] nldev_newlink+0x2b8/0x520 [ib_core]
[<ffffffffc2645fe3>] rdma_nl_rcv_msg+0x2c3/0x520 [ib_core]
[<ffffffffc264648c>]
rdma_nl_rcv_skb.constprop.0.isra.0+0x23c/0x3a0 [ib_core]
[<ffffffff9270e7b5>] netlink_unicast+0x445/0x710
[<ffffffff9270f1f1>] netlink_sendmsg+0x761/0xc40
[<ffffffff9249db29>] __sys_sendto+0x3a9/0x420
[<ffffffff9249dc8c>] __x64_sys_sendto+0xdc/0x1b0
[<ffffffff92db0ad3>] do_syscall_64+0x93/0x180
[<ffffffff92e00126>] entry_SYSCALL_64_after_hwframe+0x71/0x79

The root cause: rdma_put_gid_attr is not called when sgid_attr is set
to ERR_PTR(-ENODEV).