doc/emacs: use :code: for some missing references

It's not obvious how to reference (non-notmuch) emacs variables and
functions in a sphinx document.

diff --git a/doc/notmuch-emacs.rst b/doc/notmuch-emacs.rst
index 36dcb1162f10bd83fcb28d90022a0233142d2898..12ee25e5ba10795315dfb3e3373f5d11968693b5 100644 (file)
--- a/doc/notmuch-emacs.rst
+++ b/doc/notmuch-emacs.rst
@@ -385,10 +385,10 @@ Sending Mail
 
 :index:`mail-user-agent`
 
-       Emacs consults the variable :ref:`mail-user-agent` to choose a mail
-       sending package for commands like :ref:`report-emacs-bug` and
-       :ref:`compose-mail`.  To use ``notmuch`` for this, customize this
-       variable to the symbol :ref:`notmuch-user-agent`.
+       Emacs consults the variable :code:`mail-user-agent` to choose a mail
+       sending package for commands like :code:`report-emacs-bug` and
+       :code:`compose-mail`.  To use ``notmuch`` for this, customize this
+       variable to the symbol :code:`notmuch-user-agent`.
 
 Init File
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