The ornamental design for a controller for valves, as shown and described.
FIG. 1 is a top perspective view of a controller for valves showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a left side view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines shown in the figures are included for the purpose of illustrating portions of the controller for valves and form no part of the claimed design.