MTD: Relax dependencies

CONFIG_GENERIC_IO is just enough for the basic MTD stuff.

Signed-off-by: Richard Weinberger <richard@nod.at>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 37b05c3..8d3dac4 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -1,5 +1,6 @@
 menu "Self-contained MTD device drivers"
 	depends on MTD!=n
+	depends on HAS_IOMEM
 
 config MTD_PMC551
 	tristate "Ramix PMC551 PCI Mezzanine RAM card support"