MTD: fix pismo build error

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mtd/maps/pismo.c b/drivers/mtd/maps/pismo.c
index c48cad2..30e12c8 100644
--- a/drivers/mtd/maps/pismo.c
+++ b/drivers/mtd/maps/pismo.c
@@ -118,7 +118,7 @@
 {
 	struct platform_device *dev;
 	struct resource res = { };
-	phys_addr_t base = region.base;
+	phys_addr_t base = region->base;
 	int ret;
 
 	if (base == ~0)