Tethering: add p2p regex for shared p2p group interface

For the device does not support separate group interface,
there is only one interface, ex. p2p0, for both device and group interface.

Fixes: 141382930
Bug: 141382930
Test: atest TetheringTests
      launch GO on walleye
Change-Id: I064dd8d5dc372411ee771496813ae7c43ed037bc