The only thing that sysui exports that is used by another package are
application icons, used in desktop (windows build only). But since
gbuildification of desktop they are included directly from
$(SRCDIR)/sysui/desktop/icons instead of $(OUTDIR)/inc/icons, so the
dependency is no longer necessary.

Change-Id: I6fa3153d3793e785c1ed602c3e67c86cead2bae2