I claim the ornamental design for a fire tool, as shown and described.
FIG. 1 is a perspective view the fire tool of the present design;
FIG. 2 is an end view of the fire tool of the present design;
FIG. 3 is a top view of the fire tool of the present design; and,
FIG. 4 is a side view of the fire tool of the present design.
The broken (dashed) lines shown in FIGS. 1, 2 and 3 are included only for the purpose of illustrating environmental elements of the fire tool and form no part of the claimed design.