userspace/ppsi: pick new master, mainly we-servo things

This is the sequence of commits, in --reverse order (oldest on top):

   6cdecd8b wr-servo: bugfix for unlikely whole-second offset
   f47f5656 wrs-socket: retry getting a tx_timestamp on failure
   d8718e55 wr: trivial: add tracing of the hooks
   de0f017b proto-starndard: invalidate T1 when entering slave mode
   6be75000 proto-standard: call hook->handle_announce for all announce received
   029fbf36 wr: trivial: remove a never-used IPC command
   832bd0d5 wr-servo: move generation of the state name earlier
   11c199bc WR: set system time from WR time
   6ecdf970 wr-servo: run twice as fast
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>