Change interval units to milliseconds

Allow the monitoring intervals to be specified in
milliseconds instead of seconds in order to handle
polling intervals less than a second.

Change-Id: I3ef078df29ef2866920f00103710b02dbde6fcb2
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/power-sequencer/argument.cpp b/power-sequencer/argument.cpp
index e76adce..4e80c53 100644
--- a/power-sequencer/argument.cpp
+++ b/power-sequencer/argument.cpp
@@ -30,7 +30,7 @@
     std::cerr << "    --help                Print this menu\n";
     std::cerr << "    --action=<action>     Action: pgood-monitor "
                  "or runtime-monitor\n";
-    std::cerr << "    --interval=<interval> Interval in seconds:\n";
+    std::cerr << "    --interval=<interval> Interval in milliseconds:\n";
     std::cerr << "      PGOOD monitor:   time allowed for PGOOD to come up\n";
     std::cerr << "      Runtime monitor: polling interval.\n";