ld/

ld/
	* ldlang.c (lang_insert_orphan): Provide start/stop loadaddr syms
	rather than defining unconditionally.
	(lang_leave_overlay_section): Likewise.
	* ld.texinfo (Overlay Description): Update description and examples
	for start/stop syms.
ld/testsuite/
	* ld-elf/overlay.d: -u symbols we want to see in the output.