We claim the ornamental design for a charging cable, as shown and described.
FIG. 1 is a front perspective view of a charging cable, showing our new design;
FIG. 2 is a rear elevational view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a right-side elevational view thereof, the left-side elevational view being a mirror image thereof;
FIG. 5 is a top plan view thereof; and,
FIG. 6 is a bottom plan view thereof.
The broken lines showing a logo in FIGS. 1 and 5 and an area between two coils of a cord in FIGS. 1 and 4-6 depict environmental matter and form no part of the claimed design.