webrick: fix up r60172 and r60210

Thanks to MSP-Greg (Greg L) for helping with this.

* lib/webrick/server.rb (start_thread): properly fix non-local return
  introduced in r60208 and r60210

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60211 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/webrick/server.rb

@@ -294,13 +294,13 @@ module WEBrick
             raise
           end
           if sock.respond_to?(:sync_close=) && @config[:SSLStartImmediately]
-            begin
             WEBrick::Utils.timeout(@config[:RequestTimeout]) do
+              begin
                 sock.accept # OpenSSL::SSL::SSLSocket#accept
-              end
               rescue Errno::ECONNRESET, Errno::ECONNABORTED,
                      Errno::EPROTO, Errno::EINVAL
-              return
+                Thread.exit
+              end
             end
           end
           call_callback(:AcceptCallback, sock)