KVM: s390: vsie: Implement ASTFLEIE facility 2

KVM: s390: vsie: Implement ASTFLEIE facility 2

Implement shadowing of format-2 facility list when running in VSIE.

ASTFLEIE2 is available since IBM z16.
To function G1 has to run this KVM code and G1 and G2 have to run QEMU
with ASTFLEIE2 support.

Signed-off-by: Nina Schoetterl-Glausch <nsg@linux.ibm.com>
Co-developed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
[imbrenda@linux.ibm.com: Fix typo in comment]
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-ID: <20260612-vsie-alter-stfle-fac-v4-4-74f0e1559929@linux.ibm.com>