ARM: cleanup: debugfs error handling

Debugfs functions return NULL when they fail, or an error pointer
when not configured.  The intention behind the error pointer is that
it appears as a valid pointer to the caller, and so the caller
continues inspite of debugfs not being available.

Debugfs failure should only ever be checked with (!ptr) and not the
IS_ERR*() functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-omap2/pm-debug.c

@@ -219,7 +219,7 @@ static int __init pwrdms_setup(struct powerdomain *pwrdm, void *dir)
 		return 0;
 
 	d = debugfs_create_dir(pwrdm->name, (struct dentry *)dir);
-	if (!(IS_ERR_OR_NULL(d)))
+	if (d)
 		(void) debugfs_create_file("suspend", S_IRUGO|S_IWUSR, d,
 			(void *)pwrdm, &pwrdm_suspend_fops);
 
@@ -263,8 +263,8 @@ static int __init pm_dbg_init(void)
 		return 0;
 
 	d = debugfs_create_dir("pm_debug", NULL);
-	if (IS_ERR_OR_NULL(d))
-		return PTR_ERR(d);
+	if (!d)
+		return -EINVAL;
 
 	(void) debugfs_create_file("count", S_IRUGO,
 		d, (void *)DEBUG_FILE_COUNTERS, &debug_fops);