Add zlib to libs when finding openssl (RIPD-1496):

if openssl is configured with compression support AND you link
to the static lib, you are going to need to link to zlib.

Fundamentally the CMake finder should take care of this (as
described in https://gitlab.kitware.com/cmake/cmake/issues/16885),
but we work around it here by adding zlib explicitly. Update
beast error test for OpenSSL 1.1.0

Builds/CMake/CMakeFuncs.cmake

@@ -388,6 +388,11 @@ macro(use_openssl openssl_min)
     endif()
 
     find_package(OpenSSL)
+    # depending on how openssl is built, it might depend
+    # on zlib. In fact, the openssl find package should
+    # figure this out for us, but it does not currently...
+    # so let's add zlib ourselves to the lib list
+    find_package(ZLIB)
 
     if (static)
       set(CMAKE_FIND_LIBRARY_SUFFIXES tmp)
@@ -395,6 +400,7 @@ macro(use_openssl openssl_min)
 
     if (OPENSSL_FOUND)
       include_directories(${OPENSSL_INCLUDE_DIR})
+      list(APPEND OPENSSL_LIBRARIES ${ZLIB_LIBRARIES})
     else()
       message(FATAL_ERROR "OpenSSL not found")
     endif()