power: change from meaningless value to error number

'-1' is absolutely meaningless value.
This patch changed from meaningless value to error number.

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/power/exynos-tmu.c b/drivers/power/exynos-tmu.c
index b9968c2..6a66267 100644
--- a/drivers/power/exynos-tmu.c
+++ b/drivers/power/exynos-tmu.c
@@ -190,7 +190,7 @@
 				      COMPAT_SAMSUNG_EXYNOS_TMU);
 	if (node < 0) {
 		debug("EXYNOS_TMU: No node for tmu in device tree\n");
-		return -1;
+		return -ENODEV;
 	}
 
 	/*
@@ -202,7 +202,7 @@
 	addr = fdtdec_get_addr(blob, node, "reg");
 	if (addr == FDT_ADDR_T_NONE) {
 		debug("%s: Missing tmu-base\n", __func__);
-		return -1;
+		return -ENODEV;
 	}
 	info->tmu_base = (struct exynos5_tmu_reg *)addr;
 
@@ -246,11 +246,11 @@
 
 	if (error) {
 		debug("fail to get tmu node properties\n");
-		return -1;
+		return -EINVAL;
 	}
 #else
 	/* Non DT support may never be added. Just in case  */
-	return -1;
+	return -ENODEV;
 #endif
 
 	return 0;