Differenciate error messages to know quickly what failed

Change-Id: I4a445c345706351da8f022180d142249340acd2f
diff --git a/postprocess/packconfig/packconfig.pl b/postprocess/packconfig/packconfig.pl
index 88b8486..c5b4e90 100644
--- a/postprocess/packconfig/packconfig.pl
+++ b/postprocess/packconfig/packconfig.pl
@@ -124,7 +124,7 @@ sub get_core_files
    find_core_files($files_hash_ref);

    if ( !keys %$files_hash_ref ) {
        print_error("can't find any config files in '$files_path'", 3);
        print_error("can't find any core config files in '$files_path'", 3);
    }

    return wantarray ? @main::file_list : \@main::file_list;
@@ -149,7 +149,7 @@ sub get_lang_files
    find_lang_files($files_hash_ref, $lang);

    if ( !keys %$files_hash_ref ) {
        print_error("can't find any config files in '$files_path'", 3);
        print_error("can't find any lang config files in '$files_path'", 3);
    }

    return wantarray ? @main::file_list : \@main::file_list;