SCP: Assure that STEP is only allowed in MASTER mode remote console connections

The STEP command was inadvertently allowed to be parsed in non-master
mode connections, but it didn't actually work.  It has now been removed
from the generic remote console command table.

This was illuminated as of the discussion in #854

sim_console.c

@@ -747,7 +747,6 @@ static CTAB allowed_remote_cmds[] = {
     { "ASSIGN",   &assign_cmd,        0 },
     { "DEASSIGN", &deassign_cmd,      0 },
     { "CONTINUE", &x_continue_cmd,    0 },
-    { "STEP",     &x_step_cmd,        0 },
     { "REPEAT",   &x_repeat_cmd,      0 },
     { "COLLECT",  &x_collect_cmd,     0 },
     { "SAMPLEOUT",&x_sampleout_cmd,   0 },