glib: Fix setup hook

It was not robust against multiple matching directories, as the called
function takes exactly 3 arguments.

pkgs/development/libraries/glib/setup-hook.sh

···
 
 make_glib_find_gsettings_schemas() {
     # For packages that need gschemas of other packages (e.g. empathy)
-    if [ -d "$1"/share/gsettings-schemas/*/glib-2.0/schemas ]; then
-        addToSearchPath GSETTINGS_SCHEMAS_PATH "$1/share/gsettings-schemas/"*
-    fi
+    for maybe_dir in "$1"/share/gsettings-schemas/*/glib-2.0; do
+        if [[ -d "$maybe_dir/schemas" ]]; then
+            addToSearchPath GSETTINGS_SCHEMAS_PATH "$maybe_dir"
+        fi
+    done
 }
 addEnvHooks "$hostOffset" make_glib_find_gsettings_schemas