s390: Switch to use confidential_guest_kvm_init()

Use unified confidential_guest_kvm_init() for consistency with
other architectures.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20240229060038.606591-1-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
3 files changed