src/vendorcode: Add a README.md file

This README.md file specifies the expectations and agreements implied by
contributing code to the coreboot src/vendorcode directory.

Licenses, structure, formatting and the like are all the responsibility
of the contributors, however as the code is a part of the coreboot
codebase, members of the coreboot community are allowed to modify the
code to the extent deemed necessary.

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: Ib7e2aedce9383158d03be342cb10ae18d85146ae
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67485
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/vendorcode/README.md

@@ -0,0 +1,20 @@
+The files in the coreboot src/vendorcode subdirectory are supplied by
+various hardware and software vendors to support their platforms.  While
+these directories and files are a part of the coreboot project, their
+licenses, coding styles, and maintenance may be significantly different
+than the rest of the coreboot codebase.
+
+By contributing these directories and files to the coreboot codebase,
+the authors and copyright holders have agreed to the use and
+modification of these files by the coreboot community, however the final
+ownership and responsibility still remains with the company that
+contributed the files.
+
+The ideal goal would be to properly integrate these files into coreboot
+proper. But such undertakings should be coordinated with the owners.
+Community modification should in general be limited to fixing issues and
+adding functionality.
+
+Licenses for the files were determined by the copyright holder when the
+files were contributed.  All files here must have an open source license
+compatible with coreboot's GPL v2.