Turn if-clause into simple input check
Turn if-clause into simple input check

Makes the code more readable in my opinion.

Contributes to issue CURA-2006.

totalretribution/Cura,ynotstartups/Wanhao,hmflash/Cura,Curahelper/Cura,hmflash/Cura,fieldOfView/Cura,senttech/Cura,ynotstartups/Wanhao,senttech/Cura,Curahelper/Cura,totalretribution/Cura,fieldOfView/Cura