sci-chemistry/xcrysden: use xdg over xdg-utils

Signed-off-by: Patrick J Taylor <patrick.joseph.taylor@gmail.com>

sci-chemistry/xcrysden/xcrysden-1.6.2.ebuild

@@ -3,8 +3,7 @@
 
 EAPI=8
 
-inherit desktop
-inherit xdg-utils
+inherit desktop xdg
 
 DESCRIPTION="For the visualisation of molecular and crystal structures."
 
@@ -57,11 +56,3 @@ src_install() {
 		/usr/share/doc/${P}/examples/FermiSurface \
 		/usr/share/man/
 }
-
-pkg_postinst() {
-	xdg_icon_cache_update
-}
-
-pkg_postrm() {
-	xdg_icon_cache_update
-}