[PATCH] Add symlink from gpl-2.0.txt to a COPYING file

[Daniel P. Berrangé]

While it is good that the "Licenses/" directory contains the text
for all licenses that are applicable to u-boot code, it is harder
to determine at a glance what the default and/or preferred license
is. While humans can look at the Licenses/README file, this is not
machine parseable, making it tricky for license detection tools to
automatically determine/report on the overall / aggregate u-boot
license.

The project previously had a top level COPYING file containing a
short blurb, followed by the GPL license text. This was removed
back in commit eca3aeb352c964bdb28b8e191d6326370245e03f when
the "Licenses/" directory was introduced. For the benefit of
automated tools, it is helpful to retain a top level COPYING
file in the repository. Rather than duplicate the license text,
however, a symlink from the Licenses/gpl-2.0.txt file should
suffice.

Signed-off-by: Daniel P. Berrangé <berrange at redhat.com>
---

Some further context. This desire for a COPYING (or LICENSE)
file originates in the context of the QEMU project, which
maintains mirrors of both current upstream u-boot, and an
old fork of u-boot.

QEMU is hosted on gitlab.com and relies on GitLab's Open Source
Program which grants the project free access to the full range
of GitLab's otherwise pay-for features & resources. They have
introduced a new process for their OSS Program applications
which automatically checks if the overall license reported by
every repository is OSI approved.

Since u-boot lacks a top level COPYING or LICENSE file, GitLab
fails to identify u-boots overall license. As a result QEMU was
unable to apply for the OSS Program until removing the u-boot
mirrors, but we'd like to reinstate them.

I am somewhat uncomfortable asking u-boot maintainers to
accept this change just to work around limitations of the
commercial GitLab service. None the less the presence of a
top level COPYING / LICENSE file is a broadly accepted OSS
standard, so it is understandable that GitLab relied on
that. Using a symlink bridges between that standard and
u-boot's current Licenses dir approach in a low overhead
manner.

>From a purely cosmetic view, if looking at any u-boot mirror
on either GitLab or GitHub, AFAICS, neither are identifying
& reporting the project license, and this ought to resolve
that minor cosmetic issue.

 COPYING | 1 +
 1 file changed, 1 insertion(+)
 create mode 120000 COPYING

diff --git a/COPYING b/COPYING
new file mode 120000
index 00000000000..1ed3ba6a13c
--- /dev/null
+++ b/COPYING
@@ -0,0 +1 @@
+Licenses/gpl-2.0.txt
\ No newline at end of file
-- 
2.50.1