firmware_loader: Add sysfs nodes to monitor fw_upload

Add additional sysfs nodes to monitor the transfer of firmware upload data
to the target device:

cancel: Write 1 to cancel the data transfer
error: Display error status for a failed firmware upload
remaining_size: Display the remaining amount of data to be transferred
status: Display the progress of the firmware upload

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Tianfei zhang <tianfei.zhang@intel.com>
Tested-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Russ Weight <russell.h.weight@intel.com>
Link: https://lore.kernel.org/r/20220421212204.36052-6-russell.h.weight@intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>