PR27311, ld.bfd (symbol from plugin): undefined reference

PR27311, ld.bfd (symbol from plugin): undefined reference

A default versioned symbol definition in a shared library is
overridden by an unversioned definition in a regular object file, and
thus should not be reason to make an as-needed library needed.

bfd/
	PR 27311
	* elflink.c (_bfd_elf_add_default_symbol): Add override parameter.
	Use when handling default versioned symbol.  Rename existing
	override variable to nondef_override and use for non-default
	versioned symbol.
	(elf_link_add_object_symbols): Adjust call to suit.  Don't
	pull in as-needed libraries when override is set.
ld/
	* testsuite/ld-plugin/pr27311.d,
	* testsuite/ld-plugin/pr27311.ver,
	* testsuite/ld-plugin/pr27311a.c,
	* testsuite/ld-plugin/pr27311b.c,
	* testsuite/ld-plugin/pr27311c.c: New testcase.
	* testsuite/ld-plugin/lto.exp: Run it.  Correct PR14918 and
	PR12982 entries.