x86/pvops: remove pte_flags pvop

pte_flags() was introduced as a new pvop in order to extract just the
flags portion of a pte, which is a potentially cheaper operation than
extracting the page number as well.  It turns out this operation is
not needed, because simply using a mask to extract the flags from a
pte is sufficient for all current users.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/xen/enlighten.c

@@ -1314,7 +1314,6 @@ static const struct pv_mmu_ops xen_mmu_ops __initdata = {
 	.ptep_modify_prot_commit = __ptep_modify_prot_commit,
 
 	.pte_val = xen_pte_val,
-	.pte_flags = native_pte_flags,
 	.pgd_val = xen_pgd_val,
 
 	.make_pte = xen_make_pte,