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

This reverts commit b62c4a07 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: I9569403775730bf2219ee35aaf361371a0e961f4
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>