I claim the ornamental design for the faucet, as shown and described.
FIG. 1 is a perspective view of the faucet showing the 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 of the design being a mirror image of the right side elevational view; and,