options: Fix setting the port.

Make sure we correctly read the port from the config file.

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit bb18442fe8f58a483713eb2b988b3da9869ddf86)
connect: Check that errno is 0 to fix Windows build.

Thanks to Viktor Butskih.

Signed-off-by: Andreas Schneider <asn@cryptomilk.org>
(cherry picked from commit e051135a0516f686456b9f3d089f91ded177ef1a)
Fix the dh.c build with libgcrypt

Fixes bug reported by gentoo at https://bugs.gentoo.org/show_bug.cgi?id=533424
The function was only used by EDCSA backend which are not supported by the libgcrypt code anyway.