The ornamental design for a display mount, as shown and described.
FIG. 1 is a perspective view of a display mount showing my new design in an environment;
FIG. 2 is a perspective view thereof in another environment;
FIG. 3 is a front view of FIG. 1;
FIG. 4 is a rear view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The broken lines immediately adjacent to the shaded areas depict the bounds of the claimed design, while all other broken lines are directed to environment. The broken lines form no part of the claimed design.