[ARM] pxa: fix the warning of undeclared "struct pxaohci_platform_data"

The header file <asm/arch/ohci.h> was missing in the original file,
include it to fix the warning.

Signed-off-by: eric miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mach-pxa/devices.c b/arch/arm/mach-pxa/devices.c
index 50ff453..bfccb80 100644
--- a/arch/arm/mach-pxa/devices.c
+++ b/arch/arm/mach-pxa/devices.c
@@ -10,6 +10,7 @@
 #include <asm/arch/mmc.h>
 #include <asm/arch/irda.h>
 #include <asm/arch/i2c.h>
+#include <asm/arch/ohci.h>
 
 #include "devices.h"