examples/eventdev: fix crash on exit

examples/eventdev: fix crash on exit

This commit fixes a segfault on exit by using Ctrl^C if the master lcore
was also being used as a worker core. The root cause of the issue was
that the interrupt handler was cleaning up resources such as the ethdev
and eventdev ports, and once the interrupt handler would return, that
thread would continue working as an eventdev worker, and dereference the
memory which just had free() called on it.

Fixed by moving the cleanup code from the interrupt handler to the
cleanup stage of main(), which the master thread will execute once
it has returned from its worker() functionality.

Fixes: 085edac2ca38 ("examples/eventdev_pipeline: support Tx adapter")
Cc: stable@dpdk.org
Signed-off-by: Harry van Haaren <harry.van.haaren@intel.com>
Tested-by: Jun W Zhou <junx.w.zhou@intel.com>