platform/x86: dell-sysman: Directly use firmware_attributes_class

platform/x86: dell-sysman: Directly use firmware_attributes_class

[ Upstream commit 501d2f0e78951b9a933bbff73404b25aec45f389 ]

The usage of the lifecycle functions is not necessary anymore.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Tested-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Link: https://lore.kernel.org/r/20250104-firmware-attributes-simplify-v1-5-949f9709e405@weissschuh.net
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Stable-dep-of: 314e5ad4782d ("platform/x86: dell-wmi-sysman: Fix class device unregistration")
Signed-off-by: Sasha Levin <sashal@kernel.org>