[ Upstream commit 20589c8c ]

Failing to properly reset system registers is pretty bad. But not
quite as bad as bringing the whole machine down... So warn loudly,
but slightly more gracefully.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>