cflags: add -Wformat=2 -Wformat-overflow -Wformat-truncation
cflags: add -Wformat=2 -Wformat-overflow -Wformat-truncation

RIOT-OS/RIOT,RIOT-OS/RIOT,aeneby/RIOT,cladmi/RIOT,josephnoir/RIOT,x3ro/RIOT,toonst/RIOT,lazytech-org/RIOT,biboc/RIOT,x3ro/RIOT,A-Paul/RIOT,authmillenon/RIOT,gebart/RIOT,kbumsik/RIOT,cladmi/RIOT,A-Paul/RIOT,josephnoir/RIOT,OlegHahm/RIOT,A-Paul/RIOT,basilfx/RIOT,avmelnikoff/RIOT,toonst/RIOT,ant9000/RIOT,aeneby/RIOT,yogo1212/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,authmillenon/RIOT,basilfx/RIOT,OTAkeys/RIOT,authmillenon/RIOT,yogo1212/RIOT,rfuentess/RIOT,cladmi/RIOT,smlng/RIOT,basilfx/RIOT,basilfx/RIOT,lazytech-org/RIOT,OTAkeys/RIOT,rfuentess/RIOT,jasonatran/RIOT,mfrey/RIOT,kaspar030/RIOT,aeneby/RIOT,mtausig/RIOT,jasonatran/RIOT,BytesGalore/RIOT,kYc0o/RIOT,kYc0o/RIOT,avmelnikoff/RIOT,lazytech-org/RIOT,yogo1212/RIOT,RIOT-OS/RIOT,biboc/RIOT,x3ro/RIOT,yogo1212/RIOT,BytesGalore/RIOT,gebart/RIOT,aeneby/RIOT,kaspar030/RIOT,OlegHahm/RIOT,rfuentess/RIOT,authmillenon/RIOT,kbumsik/RIOT,OTAkeys/RIOT,toonst/RIOT,kYc0o/RIOT,authmillenon/RIOT,gebart/RIOT,mfrey/RIOT,miri64/RIOT,kbumsik/RIOT,kYc0o/RIOT,yogo1212/RIOT,mtausig/RIOT,smlng/RIOT,OTAkeys/RIOT,avmelnikoff/RIOT,basilfx/RIOT,miri64/RIOT,miri64/RIOT,rfuentess/RIOT,ant9000/RIOT,OlegHahm/RIOT,rfuentess/RIOT,OlegHahm/RIOT,BytesGalore/RIOT,smlng/RIOT,gebart/RIOT,A-Paul/RIOT,aeneby/RIOT,josephnoir/RIOT,cladmi/RIOT,BytesGalore/RIOT,BytesGalore/RIOT,RIOT-OS/RIOT,mfrey/RIOT,toonst/RIOT,biboc/RIOT,miri64/RIOT,jasonatran/RIOT,avmelnikoff/RIOT,kYc0o/RIOT,kaspar030/RIOT,yogo1212/RIOT,josephnoir/RIOT,cladmi/RIOT,mtausig/RIOT,biboc/RIOT,mtausig/RIOT,avmelnikoff/RIOT,ant9000/RIOT,x3ro/RIOT,jasonatran/RIOT,authmillenon/RIOT,kaspar030/RIOT,smlng/RIOT,lazytech-org/RIOT,ant9000/RIOT,lazytech-org/RIOT,jasonatran/RIOT,ant9000/RIOT,x3ro/RIOT,gebart/RIOT,kbumsik/RIOT,mtausig/RIOT,toonst/RIOT,josephnoir/RIOT,A-Paul/RIOT,smlng/RIOT,biboc/RIOT,RIOT-OS/RIOT,miri64/RIOT,mfrey/RIOT,kbumsik/RIOT,kaspar030/RIOT,mfrey/RIOT