Remove lib/fonts symlinking from configure

The fonts directory is removed in 5.7. Avoid creating a broken
symlink.

Change-Id: I95d1970737f54810006c084436411fc95743f72d
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>