Clean up langhooks

Clean up langhooks

	* alias.c:: Include langhooks.h.
	* emit-rtl.c: Similarly.
	* toplev.c: Similarly.
	* tree-inline.c: Similarly.
	* langhooks-def.h: New, the old langhooks.h.  Give the default
	hooks a common prefix.
	* langhooks.h: Contents extracted from toplev.h.
	* toplev.h: Move langhook stuff to langhooks.h.
	* langhooks.c: Give default hooks a common prefix.

	* c-lang.c: Include langhooks-def.h.
	* ada/misc.c: Similarly.
	* cp/cp-lang.c: Similarly.
	* f/com.c: Similarly.
	* java/lang.c: Similarly.
	* objc/objc-act.c: Similarly.

	* Makefile.in: Update.
	* ada/Makefile.in: Similarly.
	* cp/Make-lang.in: Similarly.
	* f/Make-lang.in: Similarly.
	* java/Make-lang.in: Similarly.
	* objc/Make-lang.in: Similarly.

From-SVN: r46813