I don't know of any particular command...maybe someone else does. Meanwhile, here are two workarounds.
Option 1: Doesn't ghost other notes, but makes it easy to identify the notes in the clip
1. Click on the clip in the track view.
2. Type Shift+L. This sets a loop around the clip, and when you open the PRV, you can see the loop indicator clearly above the notes you want to edit. (You can also set punch points to accomplish the same visual cue.)
Option 2: Ghosts notes that aren't in the clip you want to edit
1. Click on the track number to select all clips in the track.
2. Type K. This mutes all the clips.
3. Click on the clip you want to edit, then type K to unmute.
Any notes not in the clip you selected will be "ghosted," and it's really obvious to see the difference.