The ornamental design for a deployablefootrest, as shown and described.
FIG. 1 is a perspective view of the deployable footrest showing our new design;
FIG. 2 is a top view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a back view thereof;
FIG. 6 is a front view thereof; and
FIG. 7 is a bottom view thereof;
FIG. 8 is another perspective view thereof; and,
FIG. 9 is yet another perspective view thereof.
The broken lines showing portions of a vehicle where the deployable footrest is located are for the purpose of illustrating the environmental structure and form no part of the claimed design.