APF: delete unused code related to xlnk_event_trace

The xlnk_event_trace code was used for profiling and is not used now.
One line of the code writes a value to an SLCR register that causes
issues for non-SMP kernel

Signed-off-by: S Mohan <s.mohan@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>