The ornamental design for a headlamp, as shown and described.
FIG. 1 is a front-top perspective view of a head lamp of the present disclosure;
FIG. 2 is a rear-bottom perspective view of the head lamp shown in FIG. 1;
FIG. 3 is a front-bottom perspective view of the head lamp shown in FIG. 1;
FIG. 4 is a front elevational view of the head lamp shown in FIG. 1;
FIG. 5 is a rear elevational view of the head lamp shown in FIG. 1;
FIG. 6 is a left-side elevational view of the head lamp shown in FIG. 1;
FIG. 7 is a right-side elevational view of the head lamp shown in FIG. 1;
FIG. 8 is a top plan view of the head lamp shown in FIG. 1; and,
FIG. 9 is a bottom plan view of the head lamp shown in FIG. 1.
The broken lines immediately adjacent the shaded areas represent the bounds of the claimed design while all other broken lines depict portions of the head lamp; the broken lines form no part of the claimed design.