ssa.c: In ssa_upstream_handler, fix compile warning

src/ssa.c: In function 'ssa_upstream_handler':
src/ssa.c:1468:37: warning: comparison between 'enum ssa_conn_state' and 'enum ssa_db_phase' [-Wenum-compare]

Signed-off-by: Hal Rosenstock <hal@mellanox.com>