The ornamental design for a petfeeder, as shown and described.
FIG. 1 is a top, front, left side perspective view of a pet feeder showing my new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is an enlarged left side elevation view thereof, provided for clarity of illustration, the right side elevation view being a mirror image of the enlarged left side elevation view;
FIG. 5 is an enlarged top plan view thereof, provided for clarity of illustration; and,
FIG. 6 is an enlarged bottom plan view thereof, provided for clarity of illustration.
The broken lines in the drawings illustrate portions of the pet feeder that form no part of the claimed design.