Revert "spi: Fix deadlock when adding SPI controllers on SPI buses"

This reverts commit aa3f3d7b which is
commit 6098475d 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: I2bd07f43254864be68c6426dc3215dcd60aa0516
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>