This fixes a (harmless) use of a not re-initialized curr_order.

2020-03-27  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/94352
	* tree-ssa-propagate.c (ssa_prop_init): Move seeding of the
	worklist ...
	(ssa_propagation_engine::ssa_propagate): ... here after
	initializing curr_order.