Update release notes to 21.0.1.0+12
Sync the copy of the portable specfile with the latest update
Update openjdk_news script to specify subdirectory last
Add missing discover_trees script required by openjdk_news
Synchronise bundled versions with 21u sources (FreeType, LCMS, HarfBuzz, libpng)
Sync generate_tarball.sh with 11u & 17u version
Update bug URL for RHEL to point to the Red Hat customer portal
Fix upstream release URL for OpenJDK source
Following JDK-8005165, class data sharing can be enabled on all JIT architectures
Use tapsets from the misc tarball
Introduce 'prelease' for the portable release versioning, to handle EA builds
Make sure root installation directory is created first
Use in-place substitution for all but the first of the tapset changes
Synchronise runtime and buildtime tzdata requirements
Remove ghosts for binaries not in java-21-openjdk (pack200, rmid, unpack200)
Add missing jfr, jpackage and jwebserver alternative ghosts
Move jcmd to the headless package
Revert alt-java binary location to being within the JDK tree
Fix packaging of CDS archives
Exclude classes_nocoops.jsa on i686 and arm32
Resolves: RHEL-12998
Resolves: RHEL-14953
Resolves: RHEL-13925
Resolves: RHEL-14957
Resolves: RHEL-14945
Resolves: RHEL-11321
Resolves: RHEL-14947
