KVM: s390: selftests: Add ucontrol flic attr selftests

KVM: s390: selftests: Add ucontrol flic attr selftests

Add some superficial selftests for the floating interrupt controller
when using ucontrol VMs. These tests are intended to cover very basic
calls only.

Some of the calls may trigger null pointer dereferences on kernels not
containing the fixes in this patch series.

Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Tested-by: Hariharan Mari <hari55@linux.ibm.com>
Reviewed-by: Hariharan Mari <hari55@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20241216092140.329196-3-schlameuss@linux.ibm.com
Message-ID: <20241216092140.329196-3-schlameuss@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>