test/sma: Call waitforlisten() with proper socket argument

Currently, the test is not waiting for all the spdk_tgt instances,
but just the single one ($tgtpid). This emposes a race where first
rpc calls targeted for $t1sock may fail due to the target being
not available.

Avoid that by requesting waitforlisten() to check proper sockets.

Change-Id: I73398b14da1d5101b37057009a05363599233f38
Signed-off-by: Michal Berger <michal.berger@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/21426


Reviewed-by: Konrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Karol Latecki <karol.latecki@intel.com>
Reviewed-by: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>