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 left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is a rear view thereof; and,
FIG. 6 is a top plan view thereof.
The broken line showing of the sole, footbed, cord, strap, rear portion of shoe, buttons and portion of straps is for illustrative purposes only and forms no part of the claimed design.