As per the current implementation only single callback data gets saved per
event, driver is throwing an error if try to register multiple callback for
same event. So at time of unregistration of any event required things are
event details and callback handler as parameter of xlnx_unregister_event().

As part of adding support of multiple callbacks for same event also require
change in prototype of xlnx_unregister_event().
During unregistration of any events, now required things are event details,
callback handler and agent's private data as parameter of
xlnx_unregister_event().

Also modify the usage of xlnx_unregister_event() in xilinx/zynqmp_power.c
driver as per new implementation.
Signed-off-by: Abhyuday Godhasara <abhyuday.godhasara@xilinx.com>
Link: https://lore.kernel.org/r/20220427074803.19009-3-abhyuday.godhasara@xilinx.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>