Revert "devlink: Remove not-executed trap group notifications"

Revert "devlink: Remove not-executed trap group notifications"

This reverts commit 8bbeed4858239ac956a78e5cbaf778bd6f3baef8 as it
revealed that mlxsw and netdevsim (copy/paste from mlxsw) reregisters
devlink objects during another devlink user triggered command.

Fixes: 22849b5ea595 ("devlink: Remove not-executed trap policer notifications")
Reported-by: syzbot+93d5accfaefceedf43c1@syzkaller.appspotmail.com
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>