java/openjdk26: Add port
Includes relevant fixes for FreeBSD from mainline development, but
otherwise identical to the upstream release.
Release notes for the upstream release is here:
https://www.oracle.com/java/technologies/javase/26-relnote-issues.html
FreeBSD related fixes on top of the upstream relese:
- Serviceability Agent: fix stack traces in threads.
- Serviceability Agent: simplify implementation of procadd_read_data to read memory from process being traced.
- Serviceability Agent: symbol lookup would occationally fail for native symbols in shared objects.
Reviewed by: fuz (mentor), jrm
Approved by: fuz (mentor), jrm
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D55938