mesh: shell: Add LPN subscription commands to mesh shell
mesh: shell: Add LPN subscription commands to mesh shell

X-Original-Commit: 1409b61d162858308030c2f9c3dbd18fd0d89b73

apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble,apache/mynewt-nimble