liblights: adjust file location for smdk4210 kernel

Change-Id: Ib66a360729d25619b4270f081659b18e18437be3
diff --git a/exynos4/exynos4210/liblights/lights.c b/exynos4/exynos4210/liblights/lights.c
index 7cbe9d4..7a15a33 100644
--- a/exynos4/exynos4210/liblights/lights.c
+++ b/exynos4/exynos4210/liblights/lights.c
@@ -39,13 +39,10 @@
 static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
 static int g_enable_touchlight = -1;
 
-#ifdef EXYNOS4210_TABLET
-char const*const PANEL_FILE
-        = "/sys/class/backlight/backlight/brightness";
-#else
 char const*const PANEL_FILE
         = "/sys/class/backlight/panel/brightness";
 
+#ifndef EXYNOS4210_TABLET
 char const*const BUTTON_POWER
         = "/sys/class/sec/sec_touchkey/enable_disable";