HID: amd_sfh: Fix potential NULL pointer dereference

devm_add_action_or_reset() can suddenly invoke amd_mp2_pci_remove() at
registration that will cause NULL pointer dereference since
corresponding data is not initialized yet. The patch moves
initialization of data before devm_add_action_or_reset().

Found by Linux Driver Verification project (linuxtesting.org).

[jkosina@suse.cz: rebase]
Signed-off-by: Evgeny Novikov <novikov@ispras.ru>
Acked-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>