dcap: separate protocol name and client ip in DCapProtocolInfo#toString()

from
   DCap-3.0141.34.224.41:20009
to
   DCap-3.0,141.34.224.41:20009

Acked-by: Paul Millar
Target: master, 2.6, 2.7
Require-book: no
Require-notes: no
(cherry picked from commit 63ff338551f77e709f43fd3ea38a5fee1cf7a87c)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Merge pull request #303 from kofemann/dcap-fix-2.6

dcap: separate protocol name and client ip in DCapProtocolInfo#toString(...