Do not make tar.xz archives

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Fix comment in nsim props file

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
release: Update release script

Signed-off-by: Anton Kolesov <anton.kolesov@synopsys.com>