mtd: cs553x: Fix dependencies for !HAS_IOMEM archs

Not every arch has io memory nor can this driver ever work
on UML/i386.
So, unbreak the build by fixing the dependencies.
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

drivers/mtd/nand/Kconfig

@@ -311,6 +311,7 @@ config MTD_NAND_CAFE
 config MTD_NAND_CS553X
 	tristate "NAND support for CS5535/CS5536 (AMD Geode companion chip)"
 	depends on X86_32
+	depends on !UML && HAS_IOMEM
 	help
 	  The CS553x companion chips for the AMD Geode processor
 	  include NAND flash controllers with built-in hardware ECC