Revert BrowserExploitServer mixin

Author: jvazquez-r7

lib/msf/core/exploit/remote/browser_exploit_server.rb

@@ -598,7 +598,7 @@ def get_payload(cli, browser_info)
 
       p = regenerate_payload(cli, platform, arch)
 
-      unless p.arch.include?(arch) || p.arch.include?('cmd')
+      unless p.arch.include?(arch)
         err =  "The payload arch (#{p.arch * ", "}) is incompatible with the #{arch} target. "
         err << "Please check your payload setting."
         raise BESException, err