ACPI / battery: move some ACPI_BATTERY_* definitions to header

ACPI_BATTERY_CLASS is used in multiple places.
Also, I'll use ACPI_BATTERY_NOTIFY_STATUS inside AC driver in
one of following patches.

So, create a header file and move ACPI_BATTERY_CLASS and
ACPI_BATTERY_NOTIFY_* definitions into it.
Also, remove copy of ACPI_BATTERY_CLASS from sbs.c

Signed-off-by: Alexander Mezin <[e-mail]>
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/acpi/battery.c

···
 #include <linux/acpi.h>
 #include <linux/power_supply.h>
 
+#include "battery.h"
+
 #define PREFIX "ACPI: "
 
 #define ACPI_BATTERY_VALUE_UNKNOWN 0xFFFFFFFF
 
-#define ACPI_BATTERY_CLASS		"battery"
 #define ACPI_BATTERY_DEVICE_NAME	"Battery"
-#define ACPI_BATTERY_NOTIFY_STATUS	0x80
-#define ACPI_BATTERY_NOTIFY_INFO	0x81
-#define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82
 
 /* Battery power unit: 0 means mW, 1 means mA */
 #define ACPI_BATTERY_POWER_UNIT_MA	1

drivers/acpi/battery.h

···
+#ifndef __ACPI_BATTERY_H
+#define __ACPI_BATTERY_H
+
+#define ACPI_BATTERY_CLASS "battery"
+
+#define ACPI_BATTERY_NOTIFY_STATUS	0x80
+#define ACPI_BATTERY_NOTIFY_INFO	0x81
+#define ACPI_BATTERY_NOTIFY_THRESHOLD   0x82
+
+#endif

drivers/acpi/sbs.c

···
 #include <linux/power_supply.h>
 
 #include "sbshc.h"
+#include "battery.h"
 
 #define PREFIX "ACPI: "
 
 #define ACPI_SBS_CLASS			"sbs"
 #define ACPI_AC_CLASS			"ac_adapter"
-#define ACPI_BATTERY_CLASS		"battery"
 #define ACPI_SBS_DEVICE_NAME		"Smart Battery System"
 #define ACPI_SBS_FILE_INFO		"info"
 #define ACPI_SBS_FILE_STATE		"state"