docs(readme): update emacs instructions

Author: jimeh

README.md

@@ -86,22 +86,8 @@ lspconfig.golangci_lint_ls.setup {
 
 ### Configuration for [lsp-mode](https://github.com/emacs-lsp/lsp-mode) (Emacs)
 
-```emacs-lisp
-(with-eval-after-load 'lsp-mode
-  (lsp-register-custom-settings
-   '(("golangci-lint.command"
-      ["golangci-lint" "run" "--enable-all" "--disable" "lll" "--out-format" "json" "--issues-exit-code=1"])))
-
-  (lsp-register-client
-   (make-lsp-client :new-connection (lsp-stdio-connection
-                                     '("golangci-lint-langserver"))
-                    :activation-fn (lsp-activate-on "go")
-                    :language-id "go"
-                    :priority 0
-                    :server-id 'golangci-lint
-                    :add-on? t
-                    :library-folders-fn #'lsp-go--library-default-directories
-                    :initialization-options (lambda ()
-                                              (gethash "golangci-lint"
-                                                       (lsp-configuration-section "golangci-lint")))))
-```
+Support for golangci-lint-langserver is
+[built-in](https://github.com/emacs-lsp/lsp-mode/blob/master/clients/lsp-golangci-lint.el)
+to lsp-mode since late 2023. When the `golangci-lint-langserver` executable is
+found, it is automatically started for Go buffers as an add-on server along with
+the `gopls` language server.