The ornamental design for a seating, as shown and described.
FIG. 1 is a front perspective view of the seating showing my new design;
FIG. 2 is a front perspective view thereof shown in a closed position;
FIG. 3 is a front view thereof in an open position;
FIG. 4 is a side view, the other side being a mirror image thereof; and,
FIG. 5 is a rear view thereof.
The broken lines showing the small circular features in the middle of the backs in FIG. 5 are for the purpose of illustrating the environment of the design only and form no part of the claimed design.