No Net::Ping test in building perl-5.16.3

Due to some firewall restriction, Net::Ping tests while buiding perl caused failure with the following error: 
```
Failed 6 tests out of 2173, 99.72% okay.
	../dist/Net-Ping/t/120_udp_inst.t
	../dist/Net-Ping/t/130_tcp_inst.t
	../dist/Net-Ping/t/140_stream_inst.t
	../dist/Net-Ping/t/150_syn_inst.t
	../dist/Net-Ping/t/450_service.t
	../dist/Net-Ping/t/510_ping_udp.t
### Since not all tests were successful, you may want to run some of
### them individually and examine any diagnostic messages they produce.
### See the INSTALL document's section on "make test".
```
This patch removes Net-Ping tests from perl source code base.