Revert "spi: axi-spi-engine: Convert to platform remove callback returning void"

This reverts commit 4a680d30 which is
commit fc87abbe upstream.

It breaks the Android kernel abi and can be brought back in the future
in an abi-safe way if it is really needed.

Bug: 161946584
Change-Id: Ia869ac0e9edc46f61d2f7b6b60801984cdae1173
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>