powerpc/mm: Use a helper for finding pte bits mapping I/O area

Use a helper instead of open coding with constants. A later patch will
drop the WIMG bits and use PowerISA 3.0 defines.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/drivers/pcmcia/electra_cf.c b/drivers/pcmcia/electra_cf.c
index 61cf61a..4d7bc3f 100644
--- a/drivers/pcmcia/electra_cf.c
+++ b/drivers/pcmcia/electra_cf.c
@@ -228,7 +228,7 @@
 
 	if (!cf->mem_base || !cf->io_virt || !cf->gpio_base ||
 	    (__ioremap_at(io.start, cf->io_virt, cf->io_size,
-		_PAGE_NO_CACHE | _PAGE_GUARDED) == NULL)) {
+		  pgprot_val(pgprot_noncached(__pgprot(0)))) == NULL)) {
 		dev_err(device, "can't ioremap ranges\n");
 		status = -ENOMEM;
 		goto fail1;