In particular with the 2019 image, the time required often exceeded the
maximum of 60 minutes. Using lld reduces the runtime quite a bit (it's
still close to the limit, though).
This doesn't work with the old OpenSSL version we use with the 2015
image (that libeay32.lib file just doesn't seem to work), so continue
to use ld (the build on that image is the quickest anyway).
Tobias Brunner
7a36a8c220