iconview: fix a typo while removing the a11y adjustment weak ref
iconview: fix a typo while removing the a11y adjustment weak ref

The code sets old_adj_ptr to the location containing the old weak ref,
but then wants to remove a weak ref from &view->old_hadj, causing warnings
when disposing the widget.

jadahl/gtk,grubersjoe/adwaita,davidgumberg/gtk,Lyude/gtk-,alexlarsson/gtk,chergert/gtk,Adamovskiy/gtk,chergert/gtk,chergert/gtk,grubersjoe/adwaita,Lyude/gtk-,ahodesuka/gtk,alexlarsson/gtk,grubersjoe/adwaita,Adamovskiy/gtk,Lyude/gtk-,alexlarsson/gtk,chergert/gtk,alexlarsson/gtk,jadahl/gtk,ebassi/gtk,Adamovskiy/gtk,Distrotech/gtk2,Adamovskiy/gtk,Sidnioulz/SandboxGtk,Lyude/gtk-,jigpu/gtk,Distrotech/gtk2,bratsche/gtk-,msteinert/gtk,jadahl/gtk,jessevdk/gtk,jessevdk/gtk,ahodesuka/gtk,jessevdk/gtk,jadahl/gtk,chergert/gtk,jigpu/gtk,jadahl/gtk,msteinert/gtk,Distrotech/gtk2,davidgumberg/gtk,alexlarsson/gtk,ebassi/gtk,Lyude/gtk-,jessevdk/gtk,Adamovskiy/gtk,Sidnioulz/SandboxGtk,bratsche/gtk-,grubersjoe/adwaita,msteinert/gtk,jigpu/gtk,davidt/gtk,ebassi/gtk,grubersjoe/adwaita,msteinert/gtk,davidt/gtk,Adamovskiy/gtk,chergert/gtk,ahodesuka/gtk,jadahl/gtk,msteinert/gtk,jessevdk/gtk,davidgumberg/gtk,Distrotech/gtk2,chergert/gtk,jigpu/gtk,Lyude/gtk-,ebassi/gtk,Adamovskiy/gtk,ahodesuka/gtk,Sidnioulz/SandboxGtk,Sidnioulz/SandboxGtk,davidgumberg/gtk,davidgumberg/gtk,jigpu/gtk,bratsche/gtk-,davidt/gtk,davidt/gtk,davidgumberg/gtk,bratsche/gtk-,ahodesuka/gtk,jadahl/gtk,Distrotech/gtk2,msteinert/gtk,grubersjoe/adwaita,alexlarsson/gtk,Adamovskiy/gtk,chergert/gtk,davidgumberg/gtk,jadahl/gtk,Lyude/gtk-,davidt/gtk,ebassi/gtk,grubersjoe/adwaita,jigpu/gtk,grubersjoe/adwaita,jessevdk/gtk,jigpu/gtk,ahodesuka/gtk,Distrotech/gtk2,bratsche/gtk-,davidgumberg/gtk,Lyude/gtk-,Sidnioulz/SandboxGtk,jigpu/gtk,bratsche/gtk-,ahodesuka/gtk,ebassi/gtk,ahodesuka/gtk,jessevdk/gtk,Sidnioulz/SandboxGtk,alexlarsson/gtk,davidt/gtk,alexlarsson/gtk