SPDX: Convert all of our single license tags to Linux Kernel style

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from. So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry. Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents. There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

sunxi: power: add support for sy8106a driver

SY8106A is a PMIC which is used on the Allwinner
H3 Orange Pi Pc and Plus board. The VOUT1_SEL register is
implemented to set the default V-CPU voltage to 1200 mV.

This driver is required to ensure the SY8106A V-CPU
voltage is set to 1200 mV after a software reset. On cold
boot the default SY8106A output voltage is selected to be
1200 mV by a pair of resistors on the Orange Pi PC and Plus.

Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl>
Tested-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>