catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ic2b49715c7b81ac5bcfc12ff2d3b4c593cd95ce7
diff --git a/sensordatahandler.cpp b/sensordatahandler.cpp
index fc74b8f..4665f38 100644
--- a/sensordatahandler.cpp
+++ b/sensordatahandler.cpp
@@ -99,7 +99,7 @@
             return IPMI_CC_UNSPECIFIED_ERROR;
         }
     }
-    catch (InternalFailure& e)
+    catch (const InternalFailure& e)
     {
         commit<InternalFailure>();
         return IPMI_CC_UNSPECIFIED_ERROR;