sys/net/nanocoap: fix potential use of uinitialized variable
sys/net/nanocoap: fix potential use of uinitialized variable

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