s390: 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: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: linux-s390@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/kernel/debug.c

@@ -1056,12 +1056,6 @@ int debug_register_view(debug_info_t *id, struct debug_view *view)
 		mode &= ~(S_IWUSR | S_IWGRP | S_IWOTH);
 	pde = debugfs_create_file(view->name, mode, id->debugfs_root_entry,
 				  id, &debug_file_ops);
-	if (!pde) {
-		pr_err("Registering view %s/%s failed due to out of "
-		       "memory\n", id->name, view->name);
-		rc = -1;
-		goto out;
-	}
 	spin_lock_irqsave(&id->lock, flags);
 	for (i = 0; i < DEBUG_MAX_VIEWS; i++) {
 		if (!id->views[i])

arch/s390/kernel/kdebugfs.c

@@ -9,8 +9,6 @@ EXPORT_SYMBOL(arch_debugfs_dir);
 static int __init arch_kdebugfs_init(void)
 {
 	arch_debugfs_dir = debugfs_create_dir("s390", NULL);
-	if (IS_ERR(arch_debugfs_dir))
-		arch_debugfs_dir = NULL;
 	return 0;
 }
 postcore_initcall(arch_kdebugfs_init);

arch/s390/kernel/sysinfo.c

@@ -545,8 +545,6 @@ static __init int stsi_init_debugfs(void)
 	int lvl, i;
 
 	stsi_root = debugfs_create_dir("stsi", arch_debugfs_dir);
-	if (IS_ERR_OR_NULL(stsi_root))
-		return 0;
 	lvl = stsi(NULL, 0, 0, 0);
 	if (lvl > 0)
 		stsi_0_0_0 = lvl;