staging: vchiq_arm: make vchiq_shutdown_internal return void

The function vchiq_shutdown_internal always returns VCHIQ_SUCCESS. So change
the return type to void and simplify the logic in vchiq_shutdown.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/1621105859-30215-17-git-send-email-stefan.wahren@i2se.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>