(setf documentation) is undefined until documentation is called

[rschlatte]

Reported by Eric Marsden:

Armed Bear Common Lisp 1.2.0-dev-svn-14349
Java 1.6.0_18 Sun Microsystems Inc.
OpenJDK 64-Bit Server VM
Low-level initialization completed in 0.241 seconds.
Startup completed in 1.128 seconds.
Type ":help" for a list of available commands.
CL-USER(1): (defun foo (x) x)
FOO
CL-USER(2): (setf (documentation 'foo 'function) "Horx")
#<THREAD "interpreter" {482982BF}>: Debugger invoked on condition of type UNDEFINED-FUNCTION
  The function (SETF DOCUMENTATION) is undefined.

[rschlatte]

Reproducible for me if I start abcl with -noinit.

[rschlatte]

This is a duplicate of #266