[Integrated] RFR: Enable aarch64 build in jdk/tsan.

[Man Cao]

Changeset: aeb549dc
Author:    jie.he <10233373+jhe33 at users.noreply.github.com>
Committer: Man Cao <manc at openjdk.org>
Date:      2020-04-17 20:04:36 +0000
URL:       https://git.openjdk.java.net/tsan/commit/aeb549dc

Enable aarch64 build in jdk/tsan.

! make/autoconf/flags-cflags.m4
! make/autoconf/hotspot.m4