The ornamental design for a speakergrille, as shown and described.
FIG. 1 is a front view of a speaker grille showing my new design;
FIG. 2 is a rear view thereof; and,
FIG. 3 is a perspective view thereof.
The dot-dash broken lines illustrate an unclaimed boundary. The claimed design is indicated by the relatively dark portion in the figures, while relatively light portions outside the dot-dash broken lines form no part of the claimed design. The drawings include shadows and reflections which indicate contour, not surface ornamentation.