MINOR: stream: make stream_dump() always multi-line

MINOR: stream: make stream_dump() always multi-line

There used to be two working modes for this function, a single-line one
and a multi-line one, the difference being made on the "eol" argument
which could contain either a space or an LF (and with the prefix being
adjusted accordingly). Let's get rid of the single-line mode as it's
what limits the output contents because it's difficult to produce
exploitable structured data this way. It was only used in the rare case
of spinning streams and applets and these are the ones lacking info. Now
a spinning stream produces:

[ALERT]    (3511) : A bogus STREAM [0x227e7b0] is spinning at 5581202 calls per second and refuses to die, aborting now! Please report this error to developers:
  strm=0x227e7b0,c4a src=127.0.0.1 fe=public be=public dst=s1
  txn=0x2041650,3000 txn.req=MSG_DONE,4c txn.rsp=MSG_RPBEFORE,0
  rqf=1840000 rqa=8000 rpf=80000000 rpa=1400000
  scf=0x24af280,EST,482 scb=0x24af430,EST,1411
  af=(nil),0 sab=(nil),0
  cof=0x7fdb28026630,300:H1(0x24a6f60)/RAW((nil))/tcpv4(33)
  cob=0x23199f0,10000300:H1(0x24af630)/RAW((nil))/tcpv4(32)
  filters={}
  call trace(11):
  (...)