cgraph.h, [...]: Rename all instances of DECL_ABSTRACT to DECL_ABSTRACT_P.

cgraph.h, [...]: Rename all instances of DECL_ABSTRACT to DECL_ABSTRACT_P.

    	* cgraph.h, dbxout.c, dwarfout2.c, gimple-fold.c,
    	lto-streamer-out.c, print-tree.c, symtab.c, tree-inline.c,
    	tree-streamer-in.c, tree-streamer-out.c, tree.c, tree.h,
    	varpool.c: Rename all instances of DECL_ABSTRACT to
    	DECL_ABSTRACT_P.

    cp/
    	* class.c, decl.c, optimize.c: Rename all instances of
    	DECL_ABSTRACT to DECL_ABSTRACT_P.

    lto/
    	* lto-symtab.c, lto.c: Rename all instances of DECL_ABSTRACT to
    	DECL_ABSTRACT_P.

From-SVN: r215567