KVM: nVMX: fix comments of handle_vmon()

"VMXON pointer" is saved in vmx->nested.vmxon_ptr since
commit 3573e22 ("KVM: nVMX: additional checks on
vmxon region"). Also, handle_vmptrld() & handle_vmclear()
now have logic to check the VMCS pointer against the VMXON
pointer.

So just remove the obsolete comments of handle_vmon().

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Message-Id: <20210908171731.18885-1-yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/nested.c

@@ -4899,14 +4899,7 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
 	return -ENOMEM;
 }
 
-/*
- * Emulate the VMXON instruction.
- * Currently, we just remember that VMX is active, and do not save or even
- * inspect the argument to VMXON (the so-called "VMXON pointer") because we
- * do not currently need to store anything in that guest-allocated memory
- * region. Consequently, VMCLEAR and VMPTRLD also do not verify that the their
- * argument is different from the VMXON pointer (which the spec says they do).
- */
+/* Emulate the VMXON instruction. */
 static int handle_vmon(struct kvm_vcpu *vcpu)
 {
 	int ret;