In commit v3.6.0-rc1~100^2 (libarchive: Drop early use of crypto
library, 2016-05-03) we accidentally dropped the include directory for
OpenSSL as well as the library. Without that, it works only
accidentally when CHECK_CRYPTO happens to choose the OpenSSL
implementation and add the include directory.
Reported-by: Bradley Lowekamp <blowekamp@mail.nih.gov>