lp8727_charger: Make lp8727_charger_get_propery() simpler

Charger has only one valid property - ONLINE. If the property is not
ONLINE, then just return quickly.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>
diff --git a/drivers/power/lp8727_charger.c b/drivers/power/lp8727_charger.c
index 880bb7b..2507b2b 100644
--- a/drivers/power/lp8727_charger.c
+++ b/drivers/power/lp8727_charger.c
@@ -305,9 +305,10 @@
 {
 	struct lp8727_chg *pchg = dev_get_drvdata(psy->dev->parent);
 
-	if (psp == POWER_SUPPLY_PROP_ONLINE)
-		val->intval = lp8727_is_charger_attached(psy->name,
-							 pchg->devid);
+	if (psp != POWER_SUPPLY_PROP_ONLINE)
+		return -EINVAL;
+
+	val->intval = lp8727_is_charger_attached(psy->name, pchg->devid);
 
 	return 0;
 }