KVM: x86/mmu: Pass address space ID to TDP MMU root walkers

Move the address space ID check that is performed when iterating over
roots into the macro helpers to consolidate code.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210326021957.1424875-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>