KVM: arm64: Drop long gone function parameter documentation

update_vmid() just has one parameter "vmid".The other parameter
"kvm" is no longer used.
Signed-off-by: Peng Hao <richard.peng@oppo.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200701120709.388377-1-richard.peng@oppo.com

arch/arm64/kvm/arm.c

@@ -466,7 +466,6 @@ static bool need_new_vmid_gen(struct kvm_vmid *vmid)
 
 /**
  * update_vmid - Update the vmid with a valid VMID for the current generation
- * @kvm: The guest that struct vmid belongs to
  * @vmid: The stage-2 VMID information struct
  */
 static void update_vmid(struct kvm_vmid *vmid)