power: supply: tps65217: Switch to SPDX identifier.

Adopt the SPDX license identifier headers to ease license compliance
management.
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>

drivers/power/supply/tps65217_charger.c

-/*
- * Battery charger driver for TI's tps65217
- *
- * Copyright (c) 2015, Collabora Ltd.
-
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
-
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
- * more details.
-
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
+// SPDX-License-Identifier: GPL-2.0
+// Battery charger driver for TI's tps65217
+//
+// Copyright (C) 2015 Collabora Ltd.
+// Author: Enric Balletbo i Serra <enric.balletbo@collabora.com>
 
 /*
  * Battery charger driver for TI's tps65217