wifi: iwlwifi: fw: fix argument to efi.get_variable

We should pass the newly allocated data to fill.

Signed-off-by: Alon Giladi <alon.giladi@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230418122405.aaa6d8874442.I734841c71aad9564cb22c50f2737aaff489fadaf@changeid


Signed-off-by: Johannes Berg <johannes.berg@intel.com>