fix mingw build wiht openssl on appveyor

Jamfile

@@ -68,6 +68,8 @@ rule linking ( properties * )
 			# system starting with OpenSSL 1.1
 			result += <library>crypto <library>ssl ;
 		}
+		# boost.asio use the pre-1.1 OpenSSL API
+		result += <define>OPENSSL_API_COMPAT=0x10000000L ;
 	}
 
 	if <crypto>libcrypto in $(properties)

appveyor.yml

@@ -26,8 +26,6 @@ environment:
     compiler: gcc
     model: 32
     crypto: openssl
-    linkflags: 'linkflags="-LC:\\OpenSSL-Win32\\lib"'
-    include: 'include="c:\\OpenSSL-Win32\\include"'
 
 install:
 - if defined sim ( git submodule update --init --recursive )