Instead of having two copies of the same logic, place the power-off logic
in a separate function.

No functional changes.

Link: https://lore.kernel.org/r/64f6e8da3e5fff38b6c8fcb208ace46efe6555bb.1634812676.git.mchehab+huawei@kernel.orgSigned-off-by: NMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>
Acked-by: NXiaowei Song <songxiaowei@hisilicon.com>