lto-symtab.h (lto_symtab_prevail_decl): Do not use DECL_ABSTRACT_ORIGIN as flag we can end up using that.

2017-08-03  Richard Biener  <rguenther@suse.de>

	* lto-symtab.h (lto_symtab_prevail_decl): Do not use
	DECL_ABSTRACT_ORIGIN as flag we can end up using that.  Instead
	use DECL_LANG_FLAG_0.
	(lto_symtab_prevail_decl): Likewise.

From-SVN: r250856