Move undef FORTIFY below config.h
Move undef FORTIFY below config.h

It used to be below, then was moved on top of all, but now it's
defined in config.h. Hopefully below config.h is the right
place. config.h should never have direct includes anyway.

fgouget/spice-gtk,guodong/spice-gtk,SPICE/spice-gtk,dezelin/spice-gtk,mathslinux/spice-gtk,mathslinux/spice-gtk,elmarco/spice-gtk,dezelin/spice-gtk,guodong/spice-gtk,mathslinux/spice-gtk,dezelin/spice-gtk,Fantu/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,guodong/spice-gtk,Fantu/spice-gtk,dezelin/spice-gtk,elmarco/spice-gtk,SPICE/spice-gtk,fgouget/spice-gtk,SPICE/spice-gtk,fgouget/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,SPICE/spice-gtk,Fantu/spice-gtk,Fantu/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,mathslinux/spice-gtk,elmarco/spice-gtk,freedesktop-unofficial-mirror/spice__spice-gtk,elmarco/spice-gtk,flexVDI/spice-gtk,flexVDI/spice-gtk,guodong/spice-gtk