PEL: Allow missing AD keys in the reg callouts

In the code where the message registry can select callouts based on an
AdditionalData property value, don't trace an error messsage if it
doesn't find a matching value in the callout list.

This may be done on purpose, such as only wanting to add the ambient
temperature symbolic FRU if the sensor name passed in is the ambient
temp sensor, and not adding any callouts otherwise.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: Id45a4769fcdbb719e473ce0b414090207b62baeb
diff --git a/test/openpower-pels/registry_test.cpp b/test/openpower-pels/registry_test.cpp
index 2b5e482..be23b82 100644
--- a/test/openpower-pels/registry_test.cpp
+++ b/test/openpower-pels/registry_test.cpp
@@ -642,12 +642,12 @@
             EXPECT_EQ(callouts[0].symbolicFRUTrusted, "");
         }
         {
-            // There is no entry for PROC_NUM 2, it will fail.
+            // There is no entry for PROC_NUM 2, so no callouts
             std::vector<std::string> adData{"PROC_NUM=2"};
             AdditionalData ad{adData};
 
-            EXPECT_THROW(Registry::getCallouts(json, names, ad),
-                         std::runtime_error);
+            auto callouts = Registry::getCallouts(json, names, ad);
+            EXPECT_TRUE(callouts.empty());
         }
     }
 }