openssl/digest.rb: get rid of deprecated class

* ext/openssl/lib/openssl/digest.rb (digest, hexdigest): create
  new instance and call on it directly, to get rid of deprecated
  class OpenSSL::Digest::Digest.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44115 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/openssl/lib/openssl/digest.rb

@@ -53,8 +53,8 @@ module OpenSSL
       }
       singleton = (class << klass; self; end)
       singleton.class_eval{
-        define_method(:digest){|data| Digest.digest(name, data) }
-        define_method(:hexdigest){|data| Digest.hexdigest(name, data) }
+        define_method(:digest){|data| new.digest(data) }
+        define_method(:hexdigest){|data| new.hexdigest(data) }
       }
       const_set(name, klass)
     }

test/openssl/test_digest.rb

@@ -4,7 +4,7 @@ if defined?(OpenSSL)
 
 class OpenSSL::TestDigest < Test::Unit::TestCase
   def setup
-    @d1 = OpenSSL::Digest::Digest::new("MD5")
+    @d1 = OpenSSL::Digest.new("MD5")
     @d2 = OpenSSL::Digest::MD5.new
     @md = Digest::MD5.new
     @data = "DATA"