Documentation: KVM: KVM_GET_SUPPORTED_CPUID now exposes TSC_DEADLINE

TSC_DEADLINE is now advertised unconditionally by KVM_GET_SUPPORTED_CPUID,
since commit 9be4ec3 ("KVM: x86: Advertise TSC_DEADLINE_TIMER in
KVM_GET_SUPPORTED_CPUID", 2024-12-18).  Adjust the documentation to
reflect the new behavior.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-ID: <20250331150550.510320-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Documentation/virt/kvm/api.rst

@@ -9076,9 +9076,10 @@ the local APIC.
 
 The same is true for the ``KVM_FEATURE_PV_UNHALT`` paravirtualized feature.
 
-CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by ``KVM_GET_SUPPORTED_CPUID``.
-It can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER`` is present and the kernel
-has enabled in-kernel emulation of the local APIC.
+On older versions of Linux, CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by
+``KVM_GET_SUPPORTED_CPUID``, but it can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER``
+is present and the kernel has enabled in-kernel emulation of the local APIC.
+On newer versions, ``KVM_GET_SUPPORTED_CPUID`` does report the bit as available.
 
 CPU topology
 ~~~~~~~~~~~~