The ornamental design for an all-terrain vehicle awning, as shown and described.
FIG. 1 illustrates a top left perspective view of an all-terrain vehicle awning incorporating the new design as illustrated in the environmental setting of an exemplary side-by-side all-terrain vehicle;
FIG. 2 illustrates a top plan view of the all-terrain vehicle awning incorporating the new design;
FIG. 3 illustrates a front elevation view thereof;
FIG. 4 illustrates a bottom plan view thereof;
FIG. 5 illustrates a rear elevation view thereof;
FIG. 6 illustrates a right side elevation view thereof; and,
FIG. 7 illustrates a left side elevation view thereof.
In the drawings, the broken lines depict portions of the environment or the all-terrain vehicle awning that form no part of the claimed design.