genirq/debugfs: 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.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190122152151.16139-50-gregkh@linuxfoundation.org

kernel/irq/debugfs.c

@@ -256,8 +256,6 @@ static int __init irq_debugfs_init(void)
 	int irq;
 
 	root_dir = debugfs_create_dir("irq", NULL);
-	if (!root_dir)
-		return -ENOMEM;
 
 	irq_domain_debugfs_init(root_dir);
 

kernel/irq/irqdomain.c

@@ -1749,8 +1749,6 @@ void __init irq_domain_debugfs_init(struct dentry *root)
 	struct irq_domain *d;
 
 	domain_dir = debugfs_create_dir("domains", root);
-	if (!domain_dir)
-		return;
 
 	debugfs_create_file("default", 0444, domain_dir, NULL,
 			    &irq_domain_debug_fops);