Backport the Linkstation poweroff driver from the kernel upstream (commit a7f79f99541ef) This driver is required by the Buffalo LinkStation LS421DE for a correct power off operation. It also allows to use the WoL feature. Signed-off-by: Daniel González Cabanelas <dgcbueu@gmail.com> Signed-off-by: maurerr <mariusd84@gmail.com>