Make mlx5_cmd_exec_cb() a safe API in mlx5core.

APIs that have deferred callbacks should have some kind of cleanup
function that callers can use to fence the callbacks. Otherwise things
like module unloading can lead to dangling function pointers, or worse.

The IB MR code is the only place that calls this function and had a
really poor attempt at creating this fence. Provide a good version in
the core code as future patches will add more places that need this
fence.

Linux commit:
e355477ed9e4f401e3931043df97325d38552d54

Sponsored by:	Mellanox Technologies // NVIDIA Networking

Report EQE data upon CQ completion in mlx5core.

Report EQE data upon CQ completion to let upper layers use this data.

Linux commit:
4e0e2ea1886afe8c001971ff767f6670312a9b04

Sponsored by:	Mellanox Technologies // NVIDIA Networking

Widen EPOCH(9) usage in mlx5en(4).

Make completion event path mostly lockless using EPOCH(9).

Implement a mechanism using EPOCH(9) which allows us to make
the callback path for completion events mostly lockless.

Simplify draining callback events using epoch_wait().

While at it make sure all receive completion callbacks are
covered by the network EPOCH(9), because this is required
when calling if_input() and ether_input() after r357012.

Sponsored by:	Mellanox Technologies

mlx5_core: Import PDDR register definitions

mlx5: Restore eswitch management code from attic.

Add support for disabling and polling MSIX interrupts in mlx5core.

Sponsored by:	Mellanox Technologies

mlx5: Do not poke hardware for statistic after teardown is started.

Add sysctl(8) to get and set forward error correction, FEC, configuration
in mlx5en(4).

Sponsored by:	Mellanox Technologies

Add definition for the Port Buffer Status Register in mlx5core.

Submitted by:	kib@
Sponsored by:	Mellanox Technologies

Sort the ports registers definitions numerically in mlx5core.

Submitted by:	kib@
Sponsored by:	Mellanox Technologies