Merge branch 'devlink-move-common-flash_update-calls-to-core'

Jacob Keller says:

====================
devlink: move common flash_update calls to core

This series moves a couple common pieces done by all drivers of the
->flash_update interface into devlink.c flash update handler. Specifically,
the core code will now request_firmware and
devlink_flash_update_(begin|end)_notify.

This cleanup is intended to simplify driver implementations so that they
have less work to do and are less capable of doing the "wrong" thing.

For request_firmware, this simplification is done as it is not expected that
drivers would do anything else. It also standardizes all drivers so that
they use the same interface (request_firmware, as opposed to
request_firmware_direct), and allows reporting the netlink extended ack with
the file name attribute.

For status notification, this change prevents drivers from sending a status
message without properly sending the status end notification. The current
userspace implementation of devlink relies on this end notification to
properly close the flash update channel. Without this, the flash update
process may hang indefinitely. By moving the begin and end calls into the
core code, it is no longer possible for a driver author to get this wrong.

Changes since v3
* picked up acked-by and reviewed-by comments
* fixed the ionic driver to leave the print statement in place

For the original patch that moved request_firmware, see [1]. For the v2 see
[2]. For further discussion of the issues with devlink flash status see [3].
For v3 see [4].

[1] https://lore.kernel.org/netdev/20201113000142.3563690-1-jacob.e.keller@intel.com/
[2] https://lore.kernel.org/netdev/20201113224559.3910864-1-jacob.e.keller@intel.com/
[3] https://lore.kernel.org/netdev/6352e9d3-02af-721e-3a54-ef99a666be29@intel.com/
[4] https://lore.kernel.org/netdev/20201117200820.854115-1-jacob.e.keller@intel.com/
====================

Link: https://lore.kernel.org/r/20201118190636.1235045-1-jacob.e.keller@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>