openssl-open.xml Fix the error and improve CS (#3953)

reference/openssl/functions/openssl-open.xml

@@ -139,18 +139,20 @@
     <programlisting role="php">
 <![CDATA[
 <?php
+
 // $sealed, $env_key and $iv are assumed to contain the sealed data, our
 // envelope key and IV. All given to us by the sealer.
 
-// fetch private key from file located in private_key.pem
-$pkey = openssl_get_privatekey("file://private_key.pem);
+// Fetch private key from file located in private_key.pem
+$pkey = openssl_get_privatekey("file://private_key.pem");
 
-// decrypt the data and store it in $open
+// Decrypt the data and store it in $open
 if (openssl_open($sealed, $open, $env_key, $pkey, 'AES256', $iv)) {
-    echo "here is the opened data: ", $open;
+    echo "Here is the opened data: ", $open;
 } else {
-    echo "failed to open data";
+    echo "Failed to open data";
 }
+
 ?>
 ]]>
     </programlisting>