regulators: Remove monitoring freq from comments

Update doxygen comments to remove the exact frequency of sensor
monitoring and phase fault detection.

Currently sensors are monitored every second and phase faults are
detected every 15 seconds.  However, that could change in the future.

Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
Change-Id: I3ac39955721fde98dfe9e6059693ceeea7e504c2
diff --git a/phosphor-regulators/src/sensor_monitoring.hpp b/phosphor-regulators/src/sensor_monitoring.hpp
index 00823af..fcb02a5 100644
--- a/phosphor-regulators/src/sensor_monitoring.hpp
+++ b/phosphor-regulators/src/sensor_monitoring.hpp
@@ -40,8 +40,8 @@
  *
  * Sensor values are measured, actual values rather than target values.
  *
- * Sensors are read once per second.  The sensor values are stored on D-Bus,
- * making them available to external interfaces like Redfish.
+ * Sensors are read repeatedly based on a timer.  The sensor values are stored
+ * on D-Bus, making them available to external interfaces like Redfish.
  *
  * Sensors are read by executing actions, such as PMBusReadSensorAction.  To
  * read multiple sensors for a rail, multiple actions need to be executed.