Be more strict with Win 7 for MS14-064

The Powershell prompt can cause BAP to hang so we need to be more
strict about that.

modules/exploits/windows/browser/ms14_064_ole_code_execution.rb

@@ -56,9 +56,9 @@ class Metasploit4 < Msf::Exploit::Remote
             }
           ],
           [
-            'Other Windows x86',
+            'Windows 7 SP1',
               {
-                'os_name' => OperatingSystems::Match::WINDOWS,
+                'os_name' => OperatingSystems::Match::WINDOWS_7
               }
           ]
         ],
@@ -358,6 +358,11 @@ end function
   end
 
   def on_request_exploit(cli, request, target_info)
+    if get_target.name.match(OperatingSystems::Match::WINDOWS_7) && !datastore['AllowPowershellPrompt']
+      send_not_found(cli)
+      return
+    end
+
     case request.uri
     when /\.gif/
       if get_target.name =~ OperatingSystems::Match::WINDOWS_XP