The LWG 3529 issue changes to use two overloads instead of one with a
default argument, so that the sequence can be initialized directly with
the iterator range when no sequence argument is provided.

Signed-off-by: Jonathan Wakely <jwakely@redhat.com>

libstdc++-v3/ChangeLog:

	* include/bits/stl_queue.h (priority_queue): Construct sequence
	from iterators when no sequence argument is present (LWG 3529).
	* testsuite/23_containers/priority_queue/lwg3529.cc: New test.

Tested powerpc64le-linux. Committed to trunk.