x86: unify pte_offset_kernel

Impact: cleanup

Unify and demacro pte_offset_kernel.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 10a8c2e..c61b37a 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -509,6 +509,11 @@
 	return (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1);
 }
 
+static inline pte_t *pte_offset_kernel(pmd_t *pmd, unsigned long address)
+{
+	return (pte_t *)pmd_page_vaddr(*pmd) + pte_index(address);
+}
+
 #if PAGETABLE_LEVELS > 2
 static inline int pud_present(pud_t pud)
 {