[media] vb2-vmalloc: Protect DMA-specific code by #ifdef CONFIG_HAS_DMA

If NO_DMA=y:

drivers/built-in.o: In function `vb2_vmalloc_dmabuf_ops_detach':
videobuf2-vmalloc.c:(.text+0x6f11b0): undefined reference to `dma_unmap_sg'
drivers/built-in.o: In function `vb2_vmalloc_dmabuf_ops_map':
videobuf2-vmalloc.c:(.text+0x6f1266): undefined reference to `dma_unmap_sg'
videobuf2-vmalloc.c:(.text+0x6f1282): undefined reference to `dma_map_sg'

As we don't want to make the core VIDEOBUF2_VMALLOC depend on HAS_DMA
(it's v4l2 core code, and selected by a lot of drivers), stub out the
DMA support if HAS_DMA is not set.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/v4l2-core/videobuf2-vmalloc.c

@@ -211,6 +211,7 @@ static int vb2_vmalloc_mmap(void *buf_priv, struct vm_area_struct *vma)
 	return 0;
 }
 
+#ifdef CONFIG_HAS_DMA
 /*********************************************/
 /*         DMABUF ops for exporters          */
 /*********************************************/
@@ -380,6 +381,8 @@ static struct dma_buf *vb2_vmalloc_get_dmabuf(void *buf_priv, unsigned long flag
 
 	return dbuf;
 }
+#endif /* CONFIG_HAS_DMA */
+
 
 /*********************************************/
 /*       callbacks for DMABUF buffers        */
@@ -437,7 +440,9 @@ const struct vb2_mem_ops vb2_vmalloc_memops = {
 	.put		= vb2_vmalloc_put,
 	.get_userptr	= vb2_vmalloc_get_userptr,
 	.put_userptr	= vb2_vmalloc_put_userptr,
+#ifdef CONFIG_HAS_DMA
 	.get_dmabuf	= vb2_vmalloc_get_dmabuf,
+#endif
 	.map_dmabuf	= vb2_vmalloc_map_dmabuf,
 	.unmap_dmabuf	= vb2_vmalloc_unmap_dmabuf,
 	.attach_dmabuf	= vb2_vmalloc_attach_dmabuf,