[media] videobuf-dma-contig: use vm_iomap_memory()

vm_iomap_memory() provides a better end user interface than
remap_pfn_range(), as it does the needed tests before doing
mmap.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/v4l2-core/videobuf-dma-contig.c

@@ -305,14 +305,9 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
 		goto error;
 
 	/* Try to remap memory */
-
 	size = vma->vm_end - vma->vm_start;
-	size = (size < mem->size) ? size : mem->size;
-
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
-	retval = remap_pfn_range(vma, vma->vm_start,
-				 mem->dma_handle >> PAGE_SHIFT,
-				 size, vma->vm_page_prot);
+	retval = vm_iomap_memory(vma, vma->vm_start, size);
 	if (retval) {
 		dev_err(q->dev, "mmap: remap failed with error %d. ",
 			retval);