Clean up org-babel-expand-body: functions for awk and picolisp

* lisp/ob-awk.el (org-babel-expand-body:awk),
  lisp/ob-picolisp.el (org-babel-expand-body:picolisp): remove optional
  arg from these functions

The optional argument is apparently never passed by org-babel code.
Maybe this is a relic of an earlier calling convention?

lisp/ob-awk.el

@@ -44,7 +44,7 @@
 (defvar org-babel-awk-command "awk"
   "Name of the awk executable command.")
 
-(defun org-babel-expand-body:awk (body params &optional processed-params)
+(defun org-babel-expand-body:awk (body params)
   "Expand BODY according to PARAMS, return the expanded body."
   (dolist (pair (mapcar #'cdr (org-babel-get-header params :var)))
     (setf body (replace-regexp-in-string

lisp/ob-picolisp.el

@@ -78,7 +78,7 @@
   :version "24.1"
   :type 'string)
 
-(defun org-babel-expand-body:picolisp (body params &optional processed-params)
+(defun org-babel-expand-body:picolisp (body params)
   "Expand BODY according to PARAMS, return the expanded body."
   (let ((vars (mapcar #'cdr (org-babel-get-header params :var)))
         (result-params (cdr (assoc :result-params params)))