; Fix documentation of etc/DOC

* doc/lispref/help.texi (Documentation Basics): Doc strings of
preloaded symbols are no longer in etc/DOC.

doc/lispref/help.texi

@@ -69,14 +69,14 @@ Variables}.  The string is stored in the variable's
 @cindex @file{DOC} (documentation) file
   Sometimes, Emacs does not keep documentation strings in memory.
 There are two such circumstances.  Firstly, to save memory, the
-documentation for preloaded functions and variables (including
+documentation for primitive functions (@pxref{What Is a Function}) and
-primitives) is kept in a file named @file{DOC}, in the directory
+built-in variables is kept in a file named @file{DOC}, in the
-specified by @code{doc-directory} (@pxref{Accessing Documentation}).
+directory specified by @code{doc-directory} (@pxref{Accessing
-Secondly, when a function or variable is loaded from a byte-compiled
+Documentation}).  Secondly, when a function or variable is loaded from
-file, Emacs avoids loading its documentation string (@pxref{Docs and
+a byte-compiled file, Emacs avoids loading its documentation string
-Compilation}).  In both cases, Emacs looks up the documentation string
+(@pxref{Docs and Compilation}).  In both cases, Emacs looks up the
-from the file only when needed, such as when the user calls @kbd{C-h
+documentation string from the file only when needed, such as when the
-f} (@code{describe-function}) for a function.
+user calls @kbd{C-h f} (@code{describe-function}) for a function.
 
   Documentation strings can contain special @dfn{key substitution
 sequences}, referring to key bindings which are looked up only when