tests: add test_fmt_s32_dfp
tests: add test_fmt_s32_dfp

    + silently fix minor typos, too

RIOT-OS/RIOT,mtausig/RIOT,mfrey/RIOT,LudwigOrtmann/RIOT,biboc/RIOT,mfrey/RIOT,ks156/RIOT,roberthartung/RIOT,A-Paul/RIOT,adjih/RIOT,cladmi/RIOT,A-Paul/RIOT,lazytech-org/RIOT,rfuentess/RIOT,aeneby/RIOT,BytesGalore/RIOT,plushvoxel/RIOT,LudwigOrtmann/RIOT,jasonatran/RIOT,jasonatran/RIOT,OTAkeys/RIOT,beurdouche/RIOT,toonst/RIOT,gebart/RIOT,plushvoxel/RIOT,rfuentess/RIOT,josephnoir/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,plushvoxel/RIOT,adrianghc/RIOT,cladmi/RIOT,ant9000/RIOT,smlng/RIOT,smlng/RIOT,biboc/RIOT,yogo1212/RIOT,roberthartung/RIOT,neiljay/RIOT,A-Paul/RIOT,kYc0o/RIOT,ant9000/RIOT,yogo1212/RIOT,lazytech-org/RIOT,neiljay/RIOT,toonst/RIOT,josephnoir/RIOT,immesys/RiSyn,LudwigOrtmann/RIOT,beurdouche/RIOT,basilfx/RIOT,basilfx/RIOT,neiljay/RIOT,kerneltask/RIOT,mfrey/RIOT,kbumsik/RIOT,thomaseichinger/RIOT,plushvoxel/RIOT,immesys/RiSyn,josephnoir/RIOT,thomaseichinger/RIOT,LudwigKnuepfer/RIOT,beurdouche/RIOT,immesys/RiSyn,ant9000/RIOT,kerneltask/RIOT,authmillenon/RIOT,hamilton-mote/RIOT-OS,thomaseichinger/RIOT,LudwigKnuepfer/RIOT,kYc0o/RIOT,kaspar030/RIOT,avmelnikoff/RIOT,OlegHahm/RIOT,OTAkeys/RIOT,gebart/RIOT,basilfx/RIOT,kbumsik/RIOT,miri64/RIOT,hamilton-mote/RIOT-OS,Josar/RIOT,kerneltask/RIOT,ks156/RIOT,BytesGalore/RIOT,OlegHahm/RIOT,OTAkeys/RIOT,authmillenon/RIOT,LudwigOrtmann/RIOT,aeneby/RIOT,BytesGalore/RIOT,jasonatran/RIOT,OTAkeys/RIOT,mtausig/RIOT,rfuentess/RIOT,mtausig/RIOT,toonst/RIOT,immesys/RiSyn,adrianghc/RIOT,thomaseichinger/RIOT,adjih/RIOT,Josar/RIOT,miri64/RIOT,roberthartung/RIOT,plushvoxel/RIOT,x3ro/RIOT,kaspar030/RIOT,LudwigKnuepfer/RIOT,avmelnikoff/RIOT,kbumsik/RIOT,aeneby/RIOT,BytesGalore/RIOT,LudwigOrtmann/RIOT,adrianghc/RIOT,x3ro/RIOT,immesys/RiSyn,gebart/RIOT,hamilton-mote/RIOT-OS,x3ro/RIOT,rfuentess/RIOT,cladmi/RIOT,aeneby/RIOT,avmelnikoff/RIOT,x3ro/RIOT,adjih/RIOT,smlng/RIOT,biboc/RIOT,avmelnikoff/RIOT,hamilton-mote/RIOT-OS,x3ro/RIOT,smlng/RIOT,RIOT-OS/RIOT,toonst/RIOT,kYc0o/RIOT,rfuentess/RIOT,roberthartung/RIOT,cladmi/RIOT,RIOT-OS/RIOT,mtausig/RIOT,neiljay/RIOT,Josar/RIOT,hamilton-mote/RIOT-OS,yogo1212/RIOT,lazytech-org/RIOT,LudwigOrtmann/RIOT,adrianghc/RIOT,avmelnikoff/RIOT,kerneltask/RIOT,BytesGalore/RIOT,OlegHahm/RIOT,toonst/RIOT,kbumsik/RIOT,Josar/RIOT,A-Paul/RIOT,adjih/RIOT,kbumsik/RIOT,yogo1212/RIOT,kaspar030/RIOT,beurdouche/RIOT,kerneltask/RIOT,adjih/RIOT,basilfx/RIOT,thomaseichinger/RIOT,LudwigKnuepfer/RIOT,ks156/RIOT,aeneby/RIOT,miri64/RIOT,authmillenon/RIOT,josephnoir/RIOT,kYc0o/RIOT,mtausig/RIOT,authmillenon/RIOT,josephnoir/RIOT,mfrey/RIOT,lazytech-org/RIOT,immesys/RiSyn,kYc0o/RIOT,yogo1212/RIOT,OTAkeys/RIOT,basilfx/RIOT,cladmi/RIOT,beurdouche/RIOT,ks156/RIOT,A-Paul/RIOT,miri64/RIOT,biboc/RIOT,authmillenon/RIOT,jasonatran/RIOT,Josar/RIOT,LudwigKnuepfer/RIOT,yogo1212/RIOT,roberthartung/RIOT,neiljay/RIOT,mfrey/RIOT,authmillenon/RIOT,ks156/RIOT,gebart/RIOT,lazytech-org/RIOT,ant9000/RIOT,kaspar030/RIOT,miri64/RIOT,kaspar030/RIOT,OlegHahm/RIOT,adrianghc/RIOT,ant9000/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,smlng/RIOT,gebart/RIOT,biboc/RIOT