Enable waterCollision after moving the player above water (Fixes #3672)

apps/openmw/mwphysics/physicssystem.cpp

@@ -1349,7 +1349,8 @@ namespace MWPhysics
                 else if (physicActor->getCollisionMode() && canMoveToWaterSurface(iter->first, waterlevel))
                 {
                     const osg::Vec3f actorPosition = physicActor->getPosition();
-                    physicActor->setPosition(osg::Vec3f(actorPosition.x(), actorPosition.y(), waterlevel));            
+                    physicActor->setPosition(osg::Vec3f(actorPosition.x(), actorPosition.y(), waterlevel));
+                    waterCollision = true;
                 }
             }
             physicActor->setCanWaterWalk(waterCollision);