The ornamental design for a lightingfixture, as shown and described.
FIG. 1 is a perspective view showing the new design for a lighting fixture;
FIG. 2 is a bottom view of the lighting fixture of FIG. 1;
FIG. 3 is a top view of the lighting fixture of FIG. 1;
FIG. 4 is a left-side view of the lighting fixture of FIG. 1;
FIG. 5 is a right-side view of the lighting fixture of FIG. 1;
FIG. 6 is a front view of the lighting fixture of FIG. 1; and,
FIG. 7 is a rear view of the lighting fixture of FIG. 1.
The dashed lines showing portions of the lighting fixture are included for the purpose of illustrating environment and form no part of the claimed design. Where the figures show the article broken away, they are understood to indicate unclaimed length.