stepwise: Add ceiling type

Add a stepwise ceiling type, this is used as a
upper clipping curve to limit the max output based
on a temperature sensor. This is commonly used for
quiet fan mode where CPU throttling is allowed to
preserve a max fan noise.

Change-Id: I181d5913c92e5498a34e6d3f67cf99b67471479c
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/pid/stepwisecontroller.cpp b/pid/stepwisecontroller.cpp
index fee25ab..2408502 100644
--- a/pid/stepwisecontroller.cpp
+++ b/pid/stepwisecontroller.cpp
@@ -95,9 +95,13 @@
 
 void StepwiseController::outputProc(double value)
 {
-    // values are 10 for 10%
-    value *= 100;
-    _owner->addRPMSetPoint(value);
-
+    if (get_stepwise_info().isCeiling)
+    {
+        _owner->addRPMCeiling(value);
+    }
+    else
+    {
+        _owner->addRPMSetPoint(value);
+    }
     return;
 }