The ornamental design for a control housing for a bidet, as shown and described.
FIG. 1 is a top, side perspective view of a control housing for a bidet showing my new design separately from the bidet seat for clarity of illustration, the housing cover being shown in the open position;
FIG. 2 is a top plan view shown in a reduced scale in association with a bidet seat shown in broken lines and forming no part of the claimed design, the housing cover being shown in the closed position; and,
FIG. 3 is a side elevation view shown on a further reduced scale in association with a bidet seat shown in broken lines and forming no part thereof, the housing cover being shown in the closed position.