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 rear view thereof; and,
FIG. 6 is a top view thereof.
The broken line showing of the heel, heel cap, sole, portions of the upper, rivets, buckle, buckle holes, heel cup, and portions of the strap in the drawings show's unclaimed subject matter.