sti: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613114618.GD13119@kroah.com

drivers/gpu/drm/sti/sti_drv.c

@@ -96,7 +96,6 @@ static struct drm_info_list sti_drm_dbg_list[] = {
 
 static int sti_drm_dbg_init(struct drm_minor *minor)
 {
-	struct dentry *dentry;
 	int ret;
 
 	ret = drm_debugfs_create_files(sti_drm_dbg_list,
@@ -105,13 +104,8 @@ static int sti_drm_dbg_init(struct drm_minor *minor)
 	if (ret)
 		goto err;
 
-	dentry = debugfs_create_file("fps_show", S_IRUGO | S_IWUSR,
-				     minor->debugfs_root, minor->dev,
-				     &sti_drm_fps_fops);
-	if (!dentry) {
-		ret = -ENOMEM;
-		goto err;
-	}
+	debugfs_create_file("fps_show", S_IRUGO | S_IWUSR, minor->debugfs_root,
+			    minor->dev, &sti_drm_fps_fops);
 
 	DRM_INFO("%s: debugfs installed\n", DRIVER_NAME);
 	return 0;