powerpc: expect all devices calling dma ops to have archdata set

Now that we set archdata for of_platform and platform devices via
platform_notify() we no longer need to special case having a NULL device
pointer or NULL archdata.  It should be a driver error if this condition
shows up and the driver should be fixed.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

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

@@ -109,18 +109,8 @@ static inline struct dma_mapping_ops *get_dma_ops(struct device *dev)
 	 * only ISA DMA device we support is the floppy and we have a hack
 	 * in the floppy driver directly to get a device for us.
 	 */
-
-	if (unlikely(dev == NULL) || dev->archdata.dma_ops == NULL) {
-#ifdef CONFIG_PPC64
+	if (unlikely(dev == NULL))
 		return NULL;
-#else
-		/* Use default on 32-bit if dma_ops is not set up */
-		/* TODO: Long term, we should fix drivers so that dev and
-		 * archdata dma_ops are set up for all buses.
-		 */
-		return &dma_direct_ops;
-#endif
-	}
 
 	return dev->archdata.dma_ops;
 }