java/openjdk8: Restore workaround for aarch64 assertions

See also https://bugs.openjdk.org/browse/JDK-8247766.

Even though the upstream fix has been applied to this version of the
JDK, some users still report the assertion "guarantee(val < (1U <<
nbits)) failed: Field too big for insn" occurring, when it is built with
recent versions of clang.

Therefore, restore the workaround that uses clang 12 to build the JDK on
aarch64.

PR: 264065
MFH: 2022Q3