autoconf can't detect if AI_IDN is really supported
(907916e808/),
so a --disable-gai-idn flag was added to explicitly disable the usage
of IDN.
Before this patch, msmtp failed to send mail with the following
output:
msmtp: cannot locate host smtp.mandrillapp.com: Bad value for ai_flags
[Thomas: tweak commit log.]
Signed-off-by: Anthony Viallard <viallard@syscom-instruments.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>