The ornamental design for an accessory mount, as shown and described.
FIG. 1 is a perspective view of an accessory mount, showing our new design;
FIG. 2 is a top view thereof;
FIG. 3 is a bottom view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is a rear view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a left side view thereof;
FIG. 8 is another environmental perspective view of the accessory mount with knob fasteners; and,
FIG. 9 is another environmental perspective view of the accessory mount with a handle fastener.
The broken lines are for environmental purposes only and form no part of the claimed design. The shading illustrated in the figures is provided merely to represent the contour of the design and is not intended to be illustrative of the texture, gloss, or surface decoration.