Replace proprietary/confidential copyright notices with Apache 2.0 license, if Intel owns copyright on the relevant files

[jafingerhut]

I see many files mentioning the words "confidential" or "proprietary", or both:

cd open-p4studio
find . ! -type d -print0 | xargs -0 grep -i confidential
find . ! -type d -print0 | xargs -0 grep -i proprietary

If Intel owns the copyright on those files, and approves of releasing them under Apache 2.0 license, it would be good to change the license on those files to Apache 2.0, or some compatible license like BSD/MIT. If they can be released under an Apache 2.0 license, please add a comment line like this to the file, with appropriate comment syntax for the source language:

# SPDX-License-Identifier: Apache-2.0

If Intel does not own the copyright on those files, or cannot release them under an Apache 2.0 or other similar license, please list which problematic those files are so we can consider more carefully what to do about them.