msm: camera: Fix memory leak

CAF never deattaches the dma buffer, creating a memory leak
every time this function is run. This issue becomes increasingly
problematic as it's run a metric ton every time camera is open,
which on Coral is pretty much every time you unlock the phone
and often while you run it too. Fix it by unmaping and detaching
the dma buffer.

Reported-by: celtare21 <celtare21@gmail.com>
Signed-off-by: Demon000 <demonsingur@gmail.com>
Signed-off-by: Adam W. Willis <return.of.octobot@gmail.com>

drivers/media/platform/msm/camera/cam_smmu/cam_smmu_api.c

@@ -2415,14 +2415,13 @@ static int cam_smmu_map_stage2_buffer_and_add_to_list(int idx, int ion_fd,
 	/* add to the list */
 	list_add(&mapping_info->list, &iommu_cb_set.cb_info[idx].smmu_buf_list);
 
-	return 0;
-
 err_unmap_sg:
 	dma_buf_unmap_attachment(attach, table, dma_dir);
 err_detach:
 	dma_buf_detach(dmabuf, attach);
 err_put:
-	dma_buf_put(dmabuf);
+	if (rc)
+		dma_buf_put(dmabuf);
 err_out:
 	return rc;
 }