MIPS: Add DMA declare coherent memory support

The ohci-sm501 driver requires dma_declare_coherent_memory().  It is used
by the driver's local memory allocation with dma_alloc_coherent().

Tested on TANBAC TB0287(VR4131 + SM501).

[Ralf: Fixed reject in dma-default.c and removed the entire #if 0'ed block
 in dma-mapping.h instead of just the #if 0.]

Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/dma-mapping.h b/arch/mips/include/asm/dma-mapping.h
index d16afdd..664ba53 100644
--- a/arch/mips/include/asm/dma-mapping.h
+++ b/arch/mips/include/asm/dma-mapping.h
@@ -3,6 +3,7 @@
 
 #include <asm/scatterlist.h>
 #include <asm/cache.h>
+#include <asm-generic/dma-coherent.h>
 
 void *dma_alloc_noncoherent(struct device *dev, size_t size,
 			   dma_addr_t *dma_handle, gfp_t flag);
@@ -73,14 +74,4 @@
 extern void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
 	       enum dma_data_direction direction);
 
-#if 0
-#define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-
-extern int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
-	dma_addr_t device_addr, size_t size, int flags);
-extern void dma_release_declared_memory(struct device *dev);
-extern void * dma_mark_declared_memory_occupied(struct device *dev,
-	dma_addr_t device_addr, size_t size);
-#endif
-
 #endif /* _ASM_DMA_MAPPING_H */