gftp.desktop file should not include icon extension

[pacho2]

desktop-file-validate shows this issue:

/usr/share/applications/gftp.desktop: error: (will be fatal in the future): value "gftp.png" for key "Icon" in group "Desktop Entry" is an icon name with an extension, but there should be no extension as described in the Icon Theme Specification if the value is not an absolute path

Thanks