Revert "irqchip/imx-irqsteer: Add runtime PM support"

This reverts commit 0548b54d which is
commit 4730d223 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: I83042b752bcb6a1036e29033e836ea4adfb150aa
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>