Change 'direct-call' 'direct-callref' LIMPLE ops sematinc

Change 'direct-call' 'direct-callref' LIMPLE ops sematinc

Is cleaner to have the function c-name as first argument of
'direct-call' 'direct-callref'.  This is preparatory to anonymous
lambdas optimization.

	* lisp/emacs-lisp/comp.el (comp-propagate-insn): Use c-name when
	gathering the comp-func definition for direct calls.
	(comp-call-optim-form-call): Add put c-name as first argument of
	direct-call direct-callref when optimizing.

	* src/comp.c (emit_call): Update logic for having c-name as
	first arg of direct calls.
	(emit_call_ref): Rename 'subr_sym' into 'func'.