gnrc_tcp_pkt: fix typo in comment
gnrc_tcp_pkt: fix typo in comment

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