devlink: protect health reporter operation with instance lock

Similar to other devlink objects, protect the reporters list
by devlink instance lock. Alongside add unlocked versions
of health reporter create/destroy functions and use them in drivers
on call paths where the instance lock is held.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>