The ornamental design for wall cabinet, as shown and described.
FIG. 1 is a left front perspective view of the design of the wall cabinet; and,
FIG. 2 is a front elevational view thereof. The ornamental design is not visible in a rear view, top plan view, right or left side views or bottom view.
The characteristic feature of the ornamental design resides in the use of bands of a pattern on the doors of the wall cabinet.
The broken line showing of hardware, of legs, and of surfaces of the cabinet enclosing the doors at the top, bottom, and side edges of the doors, and the cabinet surfaces extending back from the face of the doors forms no part of the claimed design.