multistream: Support huge number of streams

multistream: Support huge number of streams

Restriction of 64K streams was limited only to L4 stream
type. In case of L3 and L2 stream type, it is possible to
define unlimited number of streams to be simulated
by traffic generator.

JIRA: VSPERF-498

Change-Id: I4ce3253299473127d135c01543999a8593b9556f
Signed-off-by: Martin Klozik <martinx.klozik@intel.com>
Reviewed-by: Al Morton <acmorton@att.com>
Reviewed-by: Christian Trautman <ctrautma@redhat.com>
Reviewed-by: Bill Michalowski <bmichalo@redhat.com>
Reviewed-by: Sridhar Rao <sridhar.rao@spirent.com>
Reviewed-by: Trevor Cooper <trevor.cooper@intel.com>