usb: ohci-pxa27x: include linux/dma-mapping.h

Include linux/dma-mapping.h to make the new functions available that are
used since 22d9d8e8 ("DMA-API: usb: use dma_set_coherent_mask()").

drivers/usb/host/ohci-pxa27x.c: In function ‘ohci_pxa_of_init’:
drivers/usb/host/ohci-pxa27x.c:310:2: error: implicit declaration of function ‘dma_coerce_mask_and_coherent’ [-Werror=implicit-function-declaration]
drivers/usb/host/ohci-pxa27x.c:310:2: error: implicit declaration of function ‘DMA_BIT_MASK’ [-Werror=implicit-function-declaration]
Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ohci-pxa27x.c

@@ -21,6 +21,7 @@
 
 #include <linux/clk.h>
 #include <linux/device.h>
+#include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>