dcmi: fix max temperature constant

Change the max temperature constant from 128 (degrees C) to 127, because
the temperature is represented with 7 bits (the 8th bit being the sign).

Change-Id: I43d2edf8235ca69a4f31a72949079601c38355b1
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
diff --git a/dcmihandler.hpp b/dcmihandler.hpp
index e23c8da..bd2c6e1 100644
--- a/dcmihandler.hpp
+++ b/dcmihandler.hpp
@@ -50,7 +50,7 @@
 {
     static constexpr auto maxDataSets = 8;
     static constexpr auto maxInstances = 255;
-    static constexpr auto maxTemp = 128; // degrees C
+    static constexpr auto maxTemp = 127; // degrees C
     static constexpr auto configFile =
         "/usr/share/ipmi-providers/dcmi_temp_readings.json";