catch exceptions as const

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ic8e6ade739bd5ea6e79cac6b9bb2b182748e10c8
diff --git a/extensions/openpower-pels/sbe_ffdc_handler.cpp b/extensions/openpower-pels/sbe_ffdc_handler.cpp
index 4415028..2fe5261 100644
--- a/extensions/openpower-pels/sbe_ffdc_handler.cpp
+++ b/extensions/openpower-pels/sbe_ffdc_handler.cpp
@@ -56,7 +56,7 @@
     {
         procPos = std::stoi((src6.value()).substr(0, 4));
     }
-    catch (std::exception& err)
+    catch (const std::exception& err)
     {
         log<level::ERR>(
             fmt::format("Conversion failure errormsg({})", err.what()).c_str());