Use GDK_KEY_KP_Decimal instead of GDK_KP_Decimal
Use GDK_KEY_KP_Decimal instead of GDK_KP_Decimal

Fixes the FTBFS introduced in 578043f97e891e423648c9f70ddf1d185f4615c4

davidgumberg/gtk,alexlarsson/gtk,jigpu/gtk,grubersjoe/adwaita,alexlarsson/gtk,jadahl/gtk,chergert/gtk,jigpu/gtk,Adamovskiy/gtk,Adamovskiy/gtk,jadahl/gtk,davidgumberg/gtk,Adamovskiy/gtk,alexlarsson/gtk,davidgumberg/gtk,jigpu/gtk,jigpu/gtk,jigpu/gtk,grubersjoe/adwaita,Adamovskiy/gtk,jigpu/gtk,grubersjoe/adwaita,chergert/gtk,chergert/gtk,grubersjoe/adwaita,davidgumberg/gtk,grubersjoe/adwaita,grubersjoe/adwaita,davidgumberg/gtk,jadahl/gtk,jigpu/gtk,alexlarsson/gtk,davidgumberg/gtk,chergert/gtk,chergert/gtk,davidgumberg/gtk,jadahl/gtk,grubersjoe/adwaita,Adamovskiy/gtk,jadahl/gtk,grubersjoe/adwaita,alexlarsson/gtk,jadahl/gtk,Adamovskiy/gtk,jadahl/gtk,chergert/gtk,alexlarsson/gtk,Adamovskiy/gtk,alexlarsson/gtk,chergert/gtk,jadahl/gtk,chergert/gtk,alexlarsson/gtk,Adamovskiy/gtk,davidgumberg/gtk,jigpu/gtk