PR libstdc++/59215
	* include/bits/shared_ptr_base.h
	(_Sp_counted_base<_S_atomic>::_M_add_ref_lock()): Use relaxed atomic
	load.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@207147 138bc75d-0d04-0410-961f-82ee72b054a4