Fixes for things found testing
Fixes for things found testing

- Fix some incorrect code noticed by Clang (and missed by GCC)

  There were some bad unsigned/signed comparisons and comparisons
  of potentially uninitialized variables.

- Ensure return to INIT in peer alive check (if dead)

  Avoid getting stuck when, as MASTER, peer death is detected and
  then a PEER_INFO message is received from the peer while in the
  MASTER_KEY_STATE. For a while, the routine would only go back to
  INIT on the initial transition from peer alive to peer dead.
  This prevented state change because a (re)transmit of KEY_SWITCH_START
  would never occur.

cmusser/vpnd