bmcweb: Session member count is zero

A botched merge conflict caused issues with the session service, and
accidentally hardcoded the session info response to a size zero
structure.  This resolves it.

Tested By:
Ran sessionService and observed sessions present

Change-Id: I1186f0416c099df5f39a9f894ccfcc20691ceb03
Signed-off-by: Ed Tanous <ed.tanous@intel.com>