The ornamental design for a bedframe, as shown and described.
FIG. 1 is a front perspective view of a bed frame showing our new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a left side elevation view thereof, the right side elevation view being a mirror image thereof; and,
FIG. 4 is a top plan view thereof.
The dashed broken lines illustrating portions of the bed frame are for environmental purposes only and form no part of the claimed design. Views of the bed frame that are not shown in the figures form no part of the claimed design.