The ornamental design for footwear, as shown and described.
FIG. 1 is a front perspective view of a shoe showing my footwear design;
FIG. 2 is a left side view of the footwear shown in FIG. 1;
FIG. 3 is a right side view of the footwear shown in FIG. 1;
FIG. 4 is a front view of the footwear shown in FIG. 1; and,
FIG. 5 is a top view of the footwear shown in FIG. 1.
The broken line showing of a sole, heel, heel cap, and rear portion of the footbed is for illustrative purposes only and forms no part of the claimed design.