catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ia9932efb6a9335e80b3f2376d2d62e1b65866f44
diff --git a/src/storagecommands.cpp b/src/storagecommands.cpp
index e9dc344..de57901 100644
--- a/src/storagecommands.cpp
+++ b/src/storagecommands.cpp
@@ -143,7 +143,7 @@
     {
         sdbusplus::message::message writeFruResp = dbus->call(writeFru);
     }
-    catch (sdbusplus::exception_t&)
+    catch (const sdbusplus::exception_t&)
     {
         // todo: log sel?
         phosphor::logging::log<phosphor::logging::level::ERR>(
@@ -315,7 +315,7 @@
                                 {
                                     message.read(path, object);
                                 }
-                                catch (sdbusplus::exception_t&)
+                                catch (const sdbusplus::exception_t&)
                                 {
                                     return;
                                 }
@@ -341,7 +341,7 @@
                                 {
                                     message.read(path, interfaces);
                                 }
-                                catch (sdbusplus::exception_t&)
+                                catch (const sdbusplus::exception_t&)
                                 {
                                     return;
                                 }
@@ -838,12 +838,12 @@
             data.push_back(static_cast<uint8_t>(
                 std::stoul(hexStr.substr(i, 2), nullptr, 16)));
         }
-        catch (std::invalid_argument& e)
+        catch (const std::invalid_argument& e)
         {
             phosphor::logging::log<phosphor::logging::level::ERR>(e.what());
             return -1;
         }
-        catch (std::out_of_range& e)
+        catch (const std::out_of_range& e)
         {
             phosphor::logging::log<phosphor::logging::level::ERR>(e.what());
             return -1;
@@ -1188,7 +1188,7 @@
     {
         sdbusplus::message::message reloadResponse = dbus->call(rsyslogReload);
     }
-    catch (sdbusplus::exception_t& e)
+    catch (const sdbusplus::exception_t& e)
     {
         phosphor::logging::log<phosphor::logging::level::ERR>(e.what());
     }