pspush: unique name for AOKP's gerrit host

  Use a unique name for the gerrit instance. This will
  prevent conflicts with other build env's if they use
  pspush as well (so long as they give a unique name
  too of course).

Change-Id: I7e96bf1f3079e8ac0083e9c549a4441148c3af34
Signed-off-by: KhasMek <Boushh@gmail.com>