The cve.mitre.org site is an archive that redirects users to cve.org.
The linked about page has also been removed, so this patch changes it to
reference the current equivalent on cve.org.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
## CVE assignment
Security bugs flagged with `security+` should have [CVE
-identifiers](http://cve.mitre.org/about/). Please reach out to the glibc
+identifiers](https://www.cve.org/About/Overview). Please reach out to the glibc
security team using the documented [security
process](https://sourceware.org/glibc/security.html) and they work on getting a
CVE number.