linux: cve-exclusions: Amend terminology

linux: cve-exclusions: Amend terminology

Replace the term 'needs backporting' with 'may need backporting' in
generate-cve-exclusions.py when the checked kernel version may or may
not be in the vulnerable version range, thus making backporting
necessary only in the former case.

In tandem we regenerate the content of cve-exclusion_6.12.inc using
https://github.com/CVEProject/cvelistV5.git repository main branch at
git hash b20d0043711588b6409ae3118bc0510ab888c316 to keep the content
in sync with the script.

Signed-off-by: Niko Mauno <niko.mauno@vaisala.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>