run: relax IP power plug recognition + serial EOF

* To communicate with IP power plug devices from Koukaam, to remote
  control power supply of test boards, don't parse minor versions, but
  support different IP power plugs
* TCL's expect may report an EOF when reading from the spawned serial
  terminal, especially when using 'socat' to stream serial over TCP/IP,
  although the spawned child is still running and delivering content.
  This problem is clearly not dependent on the characters send, but
  possibly due to strange pipe signals. When piping the serial output
  through 'tr' the problem vanishs.
foc: relax parsing of boot process termination

Until now, the successful termination of the boot process was recognized
when 'expect' saw the first L4 bootstrapper output on serial line. On sytems
with initially shaky serial connection like Versatile Express, where the serial
line baudrate changes with the bootstrapper initialization, the first expected
line might be missing. Therefore, change the expected line to the first
Fiasco.OC kernel output.