get_icon returns nothing when passed a full path

Hi, I use following snippet to get icons: ```lua local ok, devicon = pcall(require, 'nvim-web-devicons') if not ok then devicon = nil else get_icon = devicon.get_icon end local icon, hl = get_icon(t) ``` If t is `LICENSE`, everything works ok, but if it is `D:\hello\LICENSE` , failed to get icon and highlight. I think a full path end with `/LICENSE` or `\LICENSE` maybe should return the license icon and highlight.