udiskie: fix broken icons
udiskie: fix broken icons

Udiskie uses SVG icons for its tray icon. In order to load these,
librsvg needs to be included in the $GDK_PIXBUF_MODULE_FILE(loaders.cache).
Without librsvg, gdk does not support SVG images so the icons won't be
used.

If we add librsvg to buildInputs, the wrapGAppsHook will make sure that
the librsvg is included in the $GDK_PIXBUF_MODULE_FILE.

SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs