Hacks needed to make tests pass on LibreSSL.

--- a/spec/std/openssl/ssl/context_spec.cr
+++ b/spec/std/openssl/ssl/context_spec.cr
@@ -194,13 +194,13 @@
       expect_raises(ArgumentError, "missing private key") do
         OpenSSL::SSL::Context::Client.from_hash({} of String => String)
       end
-      expect_raises(OpenSSL::Error, "SSL_CTX_use_PrivateKey_file: error:02001002:system library:fopen:No such file or directory") do
+      expect_raises(OpenSSL::Error, "SSL_CTX_use_PrivateKey_file: error:02FFF002:system library:func(4095):No such file or directory") do
         OpenSSL::SSL::Context::Client.from_hash({"key" => "foo"})
       end
       expect_raises(ArgumentError, "missing certificate") do
         OpenSSL::SSL::Context::Client.from_hash({"key" => private_key})
       end
-      expect_raises(OpenSSL::Error, "SSL_CTX_use_certificate_chain_file: error:02001002:system library:fopen:No such file or directory") do
+      expect_raises(OpenSSL::Error, "SSL_CTX_use_certificate_chain_file: error:02FFF002:system library:func(4095):No such file or directory") do
         OpenSSL::SSL::Context::Client.from_hash({"key" => private_key, "cert" => "foo"})
       end
       expect_raises(ArgumentError, "Invalid SSL context: missing CA certificate") do
@@ -212,7 +212,7 @@
       expect_raises(ArgumentError, "Invalid SSL context: missing CA certificate") do
         OpenSSL::SSL::Context::Client.from_hash({"key" => private_key, "cert" => certificate, "verify_mode" => "peer"})
       end
-      expect_raises(OpenSSL::Error, "SSL_CTX_load_verify_locations: error:02001002:system library:fopen:No such file or directory") do
+      expect_raises(OpenSSL::Error, "SSL_CTX_load_verify_locations: error:02FFF002:system library:func(4095):No such file or directory") do
         OpenSSL::SSL::Context::Client.from_hash({"key" => private_key, "cert" => certificate, "ca" => "foo"})
       end
     end