drm/nouveau: sgdma: remove unused nouveau_sgdma_be::dev

nouveau_sgdma_be::dev is only set once during init and never used
anywhere, so remove it.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_sgdma.c b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
index 01707e7..ec76c0b 100644
--- a/drivers/gpu/drm/nouveau/nouveau_sgdma.c
+++ b/drivers/gpu/drm/nouveau/nouveau_sgdma.c
@@ -9,7 +9,6 @@
 	 * nouve_bo.c works properly, otherwise have to move them here
 	 */
 	struct ttm_dma_tt ttm;
-	struct drm_device *dev;
 	struct nouveau_mem *node;
 };
 
@@ -101,7 +100,6 @@
 	if (!nvbe)
 		return NULL;
 
-	nvbe->dev = drm->dev;
 	if (drm->device.info.family < NV_DEVICE_INFO_V0_TESLA)
 		nvbe->ttm.ttm.func = &nv04_sgdma_backend;
 	else