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/test/zone_mock.hpp b/test/zone_mock.hpp
index 35a6b32..4a9c3f8 100644
--- a/test/zone_mock.hpp
+++ b/test/zone_mock.hpp
@@ -13,6 +13,7 @@
 
     MOCK_METHOD1(getCachedValue, double(const std::string&));
     MOCK_METHOD1(addRPMSetPoint, void(double));
+    MOCK_METHOD1(addRPMCeiling, void(double));
     MOCK_CONST_METHOD0(getMaxRPMRequest, double());
     MOCK_CONST_METHOD0(getFailSafeMode, bool());
     MOCK_CONST_METHOD0(getFailSafePercent, double());