Does the instrumental at the end of Derek and the Dominos "Layla" have a title of its own?

Either there's no title or "Time" depending on who you believe.
Most people credit the melody to Jim Gordon, and refer to it as simply the piano coda.

The band's keyboardist Bobby Whitlock however, credits Gordon's then-girlfriend Rita Coolidge composing the main melody, as part of a song called "Time" and that Gordon ripped it off.
http://www.thegearpage.net/board/archive/index.php/t-456175.html
(entry by rongtr)

Coolidge has never claimed authorship, though she most likely wants nothing to do with Gordon, who physically abused her and ended up in prison for murder.