The ornamental design for a reversible floormat, as shown.
FIG. 1 is a top, front, left-side perspective view of a reversible floor mat.
FIG. 2 is a top plan view thereof, the bottom view being a mirror image.
FIG. 3 is a front elevation view thereof, the rear elevation view being a mirror image.
FIG. 4 is a left-side elevation view thereof, the right-side elevation view being a mirror view; and,
FIG. 5 is a top plan view thereof, shown in a position of use, the bottom view being a mirror image.
The broken lines directly adjacent to shaded areas define the boundary of the claim. All other broken lines depict portions of the reversible floor mat that form no part of the claim.