examples/ndn-ping: remove useless BOARD_BLACKLIST
examples/ndn-ping: remove useless BOARD_BLACKLIST

the ble_nimble feature is now blacklisted at package level which automatically blacklist the nrf52832 based boards

authmillenon/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,toonst/RIOT,josephnoir/RIOT,yogo1212/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,basilfx/RIOT,smlng/RIOT,OTAkeys/RIOT,josephnoir/RIOT,basilfx/RIOT,miri64/RIOT,jasonatran/RIOT,jasonatran/RIOT,toonst/RIOT,aeneby/RIOT,authmillenon/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,mtausig/RIOT,mtausig/RIOT,josephnoir/RIOT,kYc0o/RIOT,yogo1212/RIOT,OTAkeys/RIOT,OTAkeys/RIOT,yogo1212/RIOT,x3ro/RIOT,basilfx/RIOT,miri64/RIOT,aeneby/RIOT,smlng/RIOT,ant9000/RIOT,jasonatran/RIOT,josephnoir/RIOT,yogo1212/RIOT,ant9000/RIOT,ant9000/RIOT,authmillenon/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,x3ro/RIOT,toonst/RIOT,x3ro/RIOT,miri64/RIOT,ant9000/RIOT,OTAkeys/RIOT,kaspar030/RIOT,aeneby/RIOT,basilfx/RIOT,miri64/RIOT,smlng/RIOT,josephnoir/RIOT,yogo1212/RIOT,x3ro/RIOT,kaspar030/RIOT,aeneby/RIOT,x3ro/RIOT,ant9000/RIOT,kYc0o/RIOT,OlegHahm/RIOT,mtausig/RIOT,miri64/RIOT,kaspar030/RIOT,authmillenon/RIOT,smlng/RIOT,OlegHahm/RIOT,basilfx/RIOT,smlng/RIOT,OTAkeys/RIOT,aeneby/RIOT,toonst/RIOT,kYc0o/RIOT,jasonatran/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,toonst/RIOT,mtausig/RIOT,yogo1212/RIOT,mtausig/RIOT,jasonatran/RIOT,OlegHahm/RIOT,kaspar030/RIOT,OlegHahm/RIOT