rtc: palmas: Initialise bb_charging flag before using it

Initialise the variable high_bb_charging before using it to avoid
configuring wrong value and fix following compilation warning:

/*
rtc-palmas.c: In function ‘palmas_rtc_probe’:
rtc-palmas.c:242:7: warning: ‘high_bb_charging’ may be used
uninitialized in this function
*/

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/drivers/rtc/rtc-palmas.c b/drivers/rtc/rtc-palmas.c
index 3b01d56..7ea2c47 100644
--- a/drivers/rtc/rtc-palmas.c
+++ b/drivers/rtc/rtc-palmas.c
@@ -239,7 +239,7 @@
 	struct palmas_rtc *palmas_rtc = NULL;
 	int ret;
 	bool enable_bb_charging = false;
-	bool high_bb_charging;
+	bool high_bb_charging = false;
 
 	if (pdev->dev.of_node) {
 		enable_bb_charging = of_property_read_bool(pdev->dev.of_node,