The ornamental design for a cleaningadapter, as shown and described.
FIG. 1 is a left side perspective view of a cleaning adapter in accordance with the new design;
FIG. 2 is a left side elevation view thereof;
FIG. 3 is a bottom elevation view thereof;
FIG. 4 is a top elevation view thereof;
FIG. 5 is a rear view thereof; and,
FIG. 6 is a front view thereof.
The broken lines in FIGS. 1-4 and 6 are included for the purpose of illustrating a portion of the cleaning adapter that forms no part of the claimed design.