rtc: abx80x: fix RTC write bit

commit 5f1b2f77 upstream.

Fix RTC write bit as per application manual
Signed-off-by: Mitja Spes <mitja@lxnav.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/rtc/rtc-abx80x.c

@@ -28,7 +28,7 @@
 #define ABX8XX_REG_WD		0x07
 
 #define ABX8XX_REG_CTRL1	0x10
-#define ABX8XX_CTRL_WRITE	BIT(1)
+#define ABX8XX_CTRL_WRITE	BIT(0)
 #define ABX8XX_CTRL_12_24	BIT(6)
 
 #define ABX8XX_REG_CFG_KEY	0x1f