osuosl3: Add swtpm

Add a software TPM module for the openQA worker. The TPM module is
needed for the installation of Windows 11 (which is used as a basis for
testing dual boot with Debian)

(cherry picked from commit d6c9638d677711e32f65a905d76a0b0b13789cd1)
Signed-off-by: Holger Levsen <holger@layer-acht.org>