The ornamental design for a spout, as shown and described.
FIG. 1 is a perspective view of the top, front and right side of a spout showing my new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom view thereof.
The portion of the article in broken lines are shown for illustrative purposes only and form no part of the claimed design. Chain line shows the border between the part which is claimed for design registration and the other part.