kmemcheck: use kmemcheck_pte_lookup() instead of open-coding it

Lets use kmemcheck_pte_lookup() in kmemcheck_fault() instead of
open-coding it there.

Signed-off-by: Pekka Enberg <[e-mail]>
Signed-off-by: Vegard Nossum <[e-mail]>

arch/x86/mm/kmemcheck/kmemcheck.c

···
 	unsigned long error_code)
 {
 	pte_t *pte;
-	unsigned int level;
 
 	/*
 	 * XXX: Is it safe to assume that memory accesses from virtual 86
···
 	if (regs->cs != __KERNEL_CS)
 		return false;
 
-	pte = lookup_address(address, &level);
+	pte = kmemcheck_pte_lookup(address);
 	if (!pte)
-		return false;
-	if (level != PG_LEVEL_4K)
-		return false;
-	if (!pte_hidden(*pte))
 		return false;
 
 	if (error_code & 2)