We claim the ornamental design for a computing device, as shown and described.
FIG. 1 is a rear perspective view of a computing device;
FIG. 2 is a front perspective view thereof showing the computer device in an open state;
FIG. 3 is a top view thereof;
FIG. 4 is bottom view thereof;
FIG. 5 is a front view thereof;
FIG. 6 is a rear view thereof;
FIG. 7 is a right side view thereof; and,
FIG. 8 is a left side view thereof.
The dash-dash broken lines in the drawings are environmental lines which do not form part of the claimed design. The short dash-long dash lines are boundary lines which do not form part of the claimed design.