Revert "clocksource/drivers/timer-of: Remove percpu irq related code"

This reverts commit 2c78dd75 which is
commit 471ef0b5 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: Iad12df13038ddbc28ce9771f06207d284f612a5d
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>