ext/thread: SizedQueue#max= wakes up waiters properly

	* ext/thread/thread.c (rb_szqueue_max_set): use correct queue and
	  limit wakeups.  [Bug #9343][ruby-core:60517]
	* test/thread/test_queue.rb (test_sized_queue_assign_max):
	  test for bug

git-svn-id: svn+ssh://svn.ruby-lang.org/ruby/trunk@44852 b2dd03c8-39d4-4d8f-98ff-823fe69b080e