The ornamental design for a headwrap, as shown and described.
FIG. 1 is a front perspective view of a head wrap;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof; and,
FIG. 4 is a rear view of the head wrap shown in a position of use.
The broken-line outline of the partial human figure in FIG. 4 assists in illustrating how the claimed design may appear when worn, but forms no part of the claimed design.