dma-mapping: remove HAVE_ARCH_DMA_SUPPORTED

Signed-off-by: NChristoph Hellwig <hch@lst.de>

include/linux/dma-mapping.h

@@ -549,7 +549,6 @@ static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 	return 0;
 }
 
-#ifndef HAVE_ARCH_DMA_SUPPORTED
 static inline int dma_supported(struct device *dev, u64 mask)
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);
@@ -560,7 +559,6 @@ static inline int dma_supported(struct device *dev, u64 mask)
 		return 1;
 	return ops->dma_supported(dev, mask);
 }
-#endif
 
 #ifndef HAVE_ARCH_DMA_SET_MASK
 static inline int dma_set_mask(struct device *dev, u64 mask)