The ornamental design for footwear, as shown and described.
FIG. 1 is a front perspective view of footwear showing my new design;
FIG. 2 is a right side view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is a back view thereof; and,
FIG. 6 is a top view thereof.
The broken line showing of the heel, heel cap, sole, portions of the footbed, buckles, buckle holes, portions of the straps, portions of the upper, and heel cup in the drawings shows unclaimed subject matter.