IB/cache: update gid cache on client reregister event

IB/cache: update gid cache on client reregister event

Some HCAs (e.g: ConnectX4) do not trigger a IB_EVENT_GID_CHANGE on
subnet prefix update from SM (PortInfo).

Since the commit d58c23c92548 ("IB/core: Only update PKEY and GID caches
on respective events"), the GID cache is updated exclusively on
IB_EVENT_GID_CHANGE. If this event is not emitted, the subnet prefix in the
IPoIB interface’s hardware address remains set to its default value
(0xfe80000000000000).

Then rdma_bind_addr() failed because it relies on hardware address to
find the port GID (subnet_prefix + port GUID).

This patch fixes this issue by updating the GID cache on
IB_EVENT_CLIENT_REREGISTER event (emitted on PortInfo::ClientReregister=1).

Fixes: d58c23c92548 ("IB/core: Only update PKEY and GID caches on respective events")
Signed-off-by: Etienne AUJAMES <eaujames@ddn.com>
Link: https://patch.msgid.link/aVUfsO58QIDn5bGX@eaujamesFR0130
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>