The ornamental design for a lightfixture, as shown and described.
FIG. 1 is a perspective view of the light fixture showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a right side elevational view thereof; the left side elevational view being a mirror image;
FIG. 5 is a top plan view thereof; and,
FIG. 6 is a bottom plan view thereof.
The break lines shown in the drawings indicate that the appearance of any portion of the article between the break lines forms no part of the claimed design; and the broken lines illustrate portions of the light fixture that form no part of the claimed design.