[ARM] pxa: remove now unnecessary dma_needs_bounce()

With a correct dev->dma_mask before calling dmabounce_register_dev(),
dma_needs_bounce() is not necessary.

The sa1111, though, is a bit complicated. Until it's fully understood
and fixed, dma_needs_bounce() for sa1111 is kept if CONFIG_SA1111 is
enabled with no side effect (with the condition of machine_is_*)

Thanks for Mike Rapoport to fix one error in the original version of
the patch and get this tested.

Acked-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>

arch/arm/include/asm/dma-mapping.h

@@ -298,7 +298,15 @@ extern void dmabounce_unregister_dev(struct device *);
  * DMA access and 1 if the buffer needs to be bounced.
  *
  */
+#ifdef CONFIG_SA1111
 extern int dma_needs_bounce(struct device*, dma_addr_t, size_t);
+#else
+static inline int dma_needs_bounce(struct device *dev, dma_addr_t addr,
+				   size_t size)
+{
+	return 0;
+}
+#endif
 
 /*
  * The DMA API, implemented by dmabounce.c.  See below for descriptions.