catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ic2b49715c7b81ac5bcfc12ff2d3b4c593cd95ce7
diff --git a/chassishandler.cpp b/chassishandler.cpp
index dfbe004..30ffb23 100644
--- a/chassishandler.cpp
+++ b/chassishandler.cpp
@@ -277,7 +277,7 @@
                   reinterpret_cast<void*>(gatewayDetails.data()));
         payload.pack(gatewayDetails);
     }
-    catch (InternalFailure& e)
+    catch (const InternalFailure& e)
     {
         commit<InternalFailure>();
         rc = -1;
@@ -552,7 +552,7 @@
         log<level::DEBUG>("Network configuration changed",
                           entry("NETWORKCONFIG=%s", hostNetworkConfig.c_str()));
     }
-    catch (sdbusplus::exception_t& e)
+    catch (const sdbusplus::exception_t& e)
     {
         commit<InternalFailure>();
         log<level::ERR>("Error in  ipmiChassisSetSysBootOptions call");
@@ -626,7 +626,7 @@
             ipmi::getAllDbusProperties(bus, chassisCapObject.second,
                                        chassisCapObject.first, chassisCapIntf);
     }
-    catch (std::exception& e)
+    catch (const std::exception& e)
     {
         log<level::ERR>("Failed to fetch Chassis Capability properties",
                         entry("ERROR=%s", e.what()));
@@ -804,7 +804,7 @@
                               chassisCapObject.first, chassisCapIntf,
                               chassisBridgeDevAddrProp, bridgeDeviceAddr);
     }
-    catch (std::exception& e)
+    catch (const std::exception& e)
     {
         log<level::ERR>(e.what());
         return ipmi::responseUnspecifiedError();
@@ -892,7 +892,7 @@
         ipmi::setDbusProperty(*busp, service, nmiSourceObjPath, nmiSourceIntf,
                               "Enabled", value);
     }
-    catch (std::exception& e)
+    catch (const std::exception& e)
     {
         log<level::ERR>("Failed to trigger NMI_OUT",
                         entry("EXCEPTION=%s", e.what()));
@@ -1046,7 +1046,7 @@
                                                     buttonIntf, "Enabled");
         buttonDisabled = !std::get<bool>(enabled);
     }
-    catch (sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception::exception& e)
     {
         log<level::ERR>("Fail to get button Enabled property",
                         entry("PATH=%s", buttonPath.c_str()),
@@ -2039,7 +2039,7 @@
                           uint2_t{}, uint8_t{}, uint8_t{}, uint8_t{});
             return ipmi::responseSuccess(std::move(response));
         }
-        catch (InternalFailure& e)
+        catch (const InternalFailure& e)
         {
             cache::objectsPtr.reset();
             report<InternalFailure>();
@@ -2237,7 +2237,7 @@
                 return ipmi::responseInvalidFieldRequest();
             }
         }
-        catch (sdbusplus::exception_t& e)
+        catch (const sdbusplus::exception_t& e)
         {
             objectsPtr.reset();
             report<InternalFailure>();
@@ -2345,7 +2345,7 @@
         return ipmi::responseSuccess(static_cast<uint8_t>(poh::minutesPerCount),
                                      getPOHCounter());
     }
-    catch (std::exception& e)
+    catch (const std::exception& e)
     {
         log<level::ERR>(e.what());
         return ipmi::responseUnspecifiedError();
@@ -2408,7 +2408,7 @@
             return ipmi::responseUnspecifiedError();
         }
     }
-    catch (InternalFailure& e)
+    catch (const InternalFailure& e)
     {
         chassis::internal::cache::objectsPtr.reset();
         report<InternalFailure>();