RDMA/core: Fix null-ptr-deref in ibcorecleanup()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.15.78 by commit 6b3d5dcb12347f3518308c2c9d2cf72453a3e1e5, it was introduced in version v4.3 by commit 03db3a2d81e6e84f3ed3cb9e087cae17d762642b. For more details please see the references link.