[m-rev.] for review: Update list of tested platforms.

[Peter Wang]

RELEASE_NOTES:
    As above.

diff --git a/RELEASE_NOTES b/RELEASE_NOTES
index ba50b0932..e2445f4ff 100644
--- a/RELEASE_NOTES
+++ b/RELEASE_NOTES
@@ -144,12 +144,12 @@ The Mercury compiler can also compile Mercury programs to Java, C# or
 Erlang.  See README.Java, README.CSharp, and README.Erlang respectively
 for further details.
 
-The current Mercury system has been tested on Linux (x86 and x86_64),
-macOS (x86_64), and Windows (x86 and x86_64).
-For Windows, we have tested this release on Windows 7 and Windows 10.
+The current Mercury system has been tested on Linux (x86, x86_64, arm),
+macOS (x86_64), Windows 7 and Windows 10 (x86 and x86_64),
+FreeBSD (x86_64), OpenBSD (x86_64) and AIX.
 
 In the past Mercury has also been known to run on: Digital Unix,
-OSF1, IRIX 5.x, Ultrix 4.3, BSDI 1.1, AIX, HPUX, Linux (Alpha),
+OSF1, IRIX 5.x, Ultrix 4.3, BSDI 1.1, HPUX, Linux (Alpha),
 Compaq Tru64 Unix (Alpha), Solaris 2.7 (SPARC), Solaris (9),
 Mac OS X (PowerPC) and Windows 95, 98, ME, NT, 2000 and XP.
 
-- 
2.25.0