ARM: OMAP2+: Replace DEFINE_SIMPLE_ATTRIBUTE with DEFINE_DEBUGFS_ATTRIBUTE

Fix the following coccicheck warning:

./arch/arm/mach-omap2/pm-debug.c:171:0-23: WARNING: pwrdm_suspend_fops
should be defined with DEFINE_DEBUGFS_ATTRIBUTE.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

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

@@ -168,8 +168,8 @@ static int pwrdm_suspend_set(void *data, u64 val)
 	return -EINVAL;
 }
 
-DEFINE_SIMPLE_ATTRIBUTE(pwrdm_suspend_fops, pwrdm_suspend_get,
-			pwrdm_suspend_set, "%llu\n");
+DEFINE_DEBUGFS_ATTRIBUTE(pwrdm_suspend_fops, pwrdm_suspend_get,
+			  pwrdm_suspend_set, "%llu\n");
 
 static int __init pwrdms_setup(struct powerdomain *pwrdm, void *dir)
 {