drivers: base: firmware_loader: add proper SPDX identifiers on files that did not have them.

There were two files in the firmware_loader code that did not have SPDX
identifiers on them, so fix that up.

Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>