The ornamental design for a faucet, as shown and described.
FIG. 1 is a perspective view of a faucet.
FIG. 2 is a front elevation of the faucet.
FIG. 3 is a rear elevation of the faucet.
FIG. 4 is a left side elevation of the faucet.
FIG. 5 is a right side elevation of the faucet.
FIG. 6 is a top plane of the faucet; and,
FIG. 7 is a bottom plane of the faucet.
The broken line showing of FIG. 2 is for the purpose of illustrating spout of the faucet and forms no part of the claimed design. The broken line showing of FIG. 7 is for the purpose of illustrating spout and the base surface of the faucet and forms no part of the claimed design.