hw/rtc/sun4v-rtc: Relicense to GPLv2-or-later

The sun4v RTC device model added under commit a0e8930 in 2016
was unfortunately added with a license of GPL-v3-or-later, which is
not compatible with other QEMU code which has a GPL-v2-only license.

Relicense the code in the .c and the .h file to GPL-v2-or-later,
to make it compatible with the rest of QEMU.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini (for Red Hat) <pbonzini@redhat.com>
Signed-off-by: Artyom Tarasenko <atar4qemu@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20240223161300.938542-1-peter.maydell@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
(cherry picked from commit fd7f95f)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

hw/rtc/sun4v-rtc.c

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 2016 Artyom Tarasenko
  *
- * This code is licensed under the GNU GPL v3 or (at your option) any later
+ * This code is licensed under the GNU GPL v2 or (at your option) any later
  * version.
  */
 

include/hw/rtc/sun4v-rtc.h

@@ -5,7 +5,7 @@
  *
  * Copyright (c) 2016 Artyom Tarasenko
  *
- * This code is licensed under the GNU GPL v3 or (at your option) any later
+ * This code is licensed under the GNU GPL v2 or (at your option) any later
  * version.
  */