firmware_class: Log every success and failure against given device

firmware_class: Log every success and failure against given device

The hundreds of users of request_firmware() have nearly as many
different log formats for reporting failures.  They also have only the
vaguest hint as to what went wrong; only firmware_class really knows
that.  Therefore, add specific log messages for the failure modes that
aren't currently logged.

In case of a driver that tries multiple names, this may result in the
impression that it failed to initialise.  Therefore, also log successes.

This makes many error messages in drivers redundant, which will be
removed in later patches.

This does not cover the case where we fall back to a user-mode helper
(which is no longer enabled in Debian).

NOTE: hw-detect will depend on the "firmware: failed to load %s (%d)\n"
format to detect missing firmware.

Gbp-Pq: Topic bugfix/all
Gbp-Pq: Name firmware_class-log-every-success-and-failure.patch