[ARM] pxa: avoid polluting the kernel's namespace

Avoid unnecessarily pollution of the kernel's namespace by avoiding
mach/hardware.h.  Include this header file where necessary.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index a1700a80..e9b0159 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -26,11 +26,12 @@
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/mmc/host.h>
+#include <linux/io.h>
 
 #include <asm/dma.h>
-#include <asm/io.h>
 #include <asm/sizes.h>
 
+#include <mach/hardware.h>
 #include <mach/pxa-regs.h>
 #include <mach/mmc.h>