mailbox: 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: Jassi Brar <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/mailbox/bcm-flexrm-mailbox.c

···
 	struct dma_pool *bd_pool;
 	struct dma_pool *cmpl_pool;
 	struct dentry *root;
-	struct dentry *config;
-	struct dentry *stats;
 	struct mbox_controller controller;
 };
 
···
 					  1 << RING_CMPL_ALIGN_ORDER, 0);
 	if (!mbox->cmpl_pool) {
 		ret = -ENOMEM;
-		goto fail_destroy_bd_pool;
 	}
 
 	/* Allocate platform MSIs for each ring */
···
 
 	/* Create debugfs root entry */
 	mbox->root = debugfs_create_dir(dev_name(mbox->dev), NULL);
-	if (IS_ERR_OR_NULL(mbox->root)) {
-		ret = PTR_ERR_OR_ZERO(mbox->root);
-		goto fail_free_msis;
-	}
 
 	/* Create debugfs config entry */
-	mbox->config = debugfs_create_devm_seqfile(mbox->dev,
-						   "config", mbox->root,
-						   flexrm_debugfs_conf_show);
-	if (IS_ERR_OR_NULL(mbox->config)) {
-		ret = PTR_ERR_OR_ZERO(mbox->config);
-		goto fail_free_debugfs_root;
-	}
+	debugfs_create_devm_seqfile(mbox->dev, "config", mbox->root,
+				    flexrm_debugfs_conf_show);
 
 	/* Create debugfs stats entry */
-	mbox->stats = debugfs_create_devm_seqfile(mbox->dev,
-						  "stats", mbox->root,
-						  flexrm_debugfs_stats_show);
-	if (IS_ERR_OR_NULL(mbox->stats)) {
-		ret = PTR_ERR_OR_ZERO(mbox->stats);
-		goto fail_free_debugfs_root;
-	}
+	debugfs_create_devm_seqfile(mbox->dev, "stats", mbox->root,
+				    flexrm_debugfs_stats_show);
+
 skip_debugfs:
 
 	/* Initialize mailbox controller */
···
 
 fail_free_debugfs_root:
 	debugfs_remove_recursive(mbox->root);
-fail_free_msis:
 	platform_msi_domain_free_irqs(dev);
 fail_destroy_cmpl_pool:
 	dma_pool_destroy(mbox->cmpl_pool);
-fail_destroy_bd_pool:
 	dma_pool_destroy(mbox->bd_pool);
 fail:
 	return ret;

drivers/mailbox/bcm-pdc-mailbox.c

···
 	 */
 	struct scatterlist *src_sg[PDC_RING_ENTRIES];
 
-	struct dentry *debugfs_stats;  /* debug FS stats file for this PDC */
-
 	/* counters */
 	u32  pdc_requests;     /* number of request messages submitted */
 	u32  pdc_replies;      /* number of reply messages received */
···
 		debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
 
 	/* S_IRUSR == 0400 */
-	pdcs->debugfs_stats = debugfs_create_file(spu_stats_name, 0400,
-						  debugfs_dir, pdcs,
-						  &pdc_debugfs_stats);
+	debugfs_create_file(spu_stats_name, 0400, debugfs_dir, pdcs,
+			    &pdc_debugfs_stats);
 }
 
 static void pdc_free_debugfs(void)
···
 	if (err)
 		goto cleanup_buf_pool;
 
-	pdcs->debugfs_stats = NULL;
 	pdc_setup_debugfs(pdcs);
 
 	dev_dbg(dev, "pdc_probe() successful");