Give KVM x86 the same treatment as all other KVM architectures, and
officially take ownership of x86 specific KVM selftests (changes have
been routed through kvm and/or kvm-x86 for quite some time).

Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20230817234114.1420092-1-seanjc@google.com


Signed-off-by: Sean Christopherson <seanjc@google.com>