dma-mapping: mark dma_supported static

Now that the remaining users in drivers are gone, this function can be
marked static.
Signed-off-by: Christoph Hellwig <hch@lst.de>

include/linux/dma-mapping.h

@@ -139,7 +139,6 @@ int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
 		unsigned long attrs);
 bool dma_can_mmap(struct device *dev);
-int dma_supported(struct device *dev, u64 mask);
 bool dma_pci_p2pdma_supported(struct device *dev);
 int dma_set_mask(struct device *dev, u64 mask);
 int dma_set_coherent_mask(struct device *dev, u64 mask);
@@ -248,10 +247,6 @@ static inline bool dma_can_mmap(struct device *dev)
 {
 	return false;
 }
-static inline int dma_supported(struct device *dev, u64 mask)
-{
-	return 0;
-}
 static inline bool dma_pci_p2pdma_supported(struct device *dev)
 {
 	return false;

kernel/dma/mapping.c

@@ -707,7 +707,7 @@ int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
 }
 EXPORT_SYMBOL_GPL(dma_mmap_noncontiguous);
 
-int dma_supported(struct device *dev, u64 mask)
+static int dma_supported(struct device *dev, u64 mask)
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 
@@ -721,7 +721,6 @@ int dma_supported(struct device *dev, u64 mask)
 		return 1;
 	return ops->dma_supported(dev, mask);
 }
-EXPORT_SYMBOL(dma_supported);
 
 bool dma_pci_p2pdma_supported(struct device *dev)
 {