Revert "don't return depots unconditionally"

This reverts commit 8c3c9d9f8e.

src/unit/unit_find.cpp

@@ -208,6 +208,10 @@ class BestDepotFinder
 					return;
 				}
 
+				if (this->best_dist == INT_MAX) {
+					this->best_depot = dest;
+				}
+
 				if (distance >= this->best_dist) {
 					//if the depot's simple distance is greater or equal to the real travel distance of the currently-chosen depot, then it can never be closer than it, and we have no reason to actually calculate its real travel distance 
 					return;