drm/msm/dsi: correct DSI id bounds check during registration

Check DSI instance id argument against the proper boundary size
to protect against invalid configuration of the DSI id.

Signed-off-by: Lloyd Atkinson <latkinso@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index 1a54fd6..4cb1cb6 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -862,7 +862,7 @@
 	int id = msm_dsi->id;
 	int ret;
 
-	if (id > DSI_MAX) {
+	if (id >= DSI_MAX) {
 		pr_err("%s: invalid id %d\n", __func__, id);
 		return -EINVAL;
 	}