Removing the location icon from postcode forms

example - https://www.gov.uk/recycling-collections

This layout is broken on mobile and after discussing with designers
it was agreed that this icon is superfluous. So I've removed it

https://www.pivotaltracker.com/story/show/73192808
Does anything else use `icon-locator.png`, if not could we remove that to cleanup assets as we go? (same for the 2x icon as well)