SPDX moved from GPL-2.0 to GPL-2.0-only and from GPL-2.0+ to
GPL-2.0-or-later. Reflect that in the SPDX license headers.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
The DTS files in files-4.19 and files-5.4 are exactly identical
except for one file (armada-3720-uDPU.dts), which is only present
for 4.19, as it has been upstreamed before 5.4.
Since there is no point in maintaining all these identical files
twice, this patch moves them to the "files" directory, only keeping
the named exception to files-4.19.
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>