package/dovecot-pigeonhole: bump version to 0.5.11
Release notes:
https://dovecot.org/pipermail/dovecot-news/2020-August/000439.html
Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit bbb4e2104606bc55ba070d53cc4d90c878ef74b3)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>