stm32_common/flashpage: remove repeated command
stm32_common/flashpage: remove repeated command

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