Buildroot commit dcee99507c bumped icu
from version 73-2 to 77-1 causing a build error during linking.
Upstream is not expected to backport this patch to 2.3.x:
https://dovecot.org/mailman3/archives/list/dovecot@dovecot.org/thread/VT7D6XWB5ZRL7KIER445D3JR464CALPU/
Fixes:
https://autobuild.buildroot.org/results/94fc2de03b5d6afd32c457be7faf0ac06cc37212/
Signed-off-by: Bernd Kuhls <bernd@kuhls.net>
Signed-off-by: Julien Olivain <ju.o@free.fr>