gpu: host1x: Set up device DMA parameters

In order to store device DMA parameters, the DMA framework depends on
the device's dma_parms field to point at a valid memory location. Add
backing storage for this in struct host1x_memory_context and point to
it.

Reported-by: Jonathan Hunter <[e-mail]>
Reviewed-by: Christoph Hellwig <[e-mail]>
Tested-by: Jon Hunter <[e-mail]>
Signed-off-by: Thierry Reding <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/host1x/context.c

···
 		ctx->dev.parent = host1x->dev;
 		ctx->dev.release = host1x_memory_context_release;
 
+		ctx->dev.dma_parms = &ctx->dma_parms;
 		dma_set_max_seg_size(&ctx->dev, UINT_MAX);
 
 		err = device_add(&ctx->dev);

include/linux/host1x.h

···
 	refcount_t ref;
 	struct pid *owner;
 
+	struct device_dma_parameters dma_parms;
 	struct device dev;
 	u64 dma_mask;
 	u32 stream_id;