re PR libstdc++/54352 (relaxed data race rules for ~condition_variable_any)

re PR libstdc++/54352 (relaxed data race rules for ~condition_variable_any)

	PR libstdc++/54352
	* include/std/condition_variable (condition_variable_any): Move into
	inline namespace _V2 and replace mutex member with shared_ptr<mutex>.
	* src/c++11/condition_variable.cc (condition_variable_any): Move
	definitions to ...
	* src/c++11/compatibility-condvar.cc (condition_variable_any): Here.
	* src/Makefile.am: Add new source file.
	* src/Makefile.in: Regenerate.

From-SVN: r201112