MIPS: Use bool function return values of true/false not 1/0

Use the normal return values for bool functions
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9640/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

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

@@ -23,7 +23,7 @@ static inline struct dma_map_ops *get_dma_ops(struct device *dev)
 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
 {
 	if (!dev->dma_mask)
-		return 0;
+		return false;
 
 	return addr + size <= *dev->dma_mask;
 }