The ornamental design for a dunnage accessory, as shown and described.
FIG. 1 is a perspective view of a dunnage accessory showing my new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a right side elevation view thereof;
FIG. 5 is a left side elevation view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is a front elevation view thereof, showing a portion of dunnage received therein.
The broken line shown in the figures are for the purpose of illustrating portions of the dunnage accessory that form no part of the claimed design. The broken lines showing a portion of dunnage in FIG. 8 are for the purpose of illustrating environment and form no part of the claimed design.