staging: vchiq_arm: Make vchiq_shutdown never fail

[ Upstream commit f2b8ebfb ]

Most of the users of vchiq_shutdown ignore the return value,
which is bad because this could lead to resource leaks.
So instead of changing all calls to vchiq_shutdown, it's easier
to make vchiq_shutdown never fail.

Fixes: 71bad7f0 ("staging: add bcm2708 vchiq driver")
Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/20250715161108.3411-4-wahrenst@gmx.net


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>