Update filter list for custom xref query

Rebar has support for optional compilers built-in. These compilers might
not be installed causing xref to return errors for the undefined external
function calls query. The updated filter list will catch this error and
act as a nop if they are installed.

rebar.config

@@ -5,6 +5,11 @@
 {erl_opts, [warnings_as_errors]}.
 {xref_checks, []}.
 {xref_queries,
-  [{"(XC - UC) || (XU - X - B
+ [{"(XC - UC) || (XU - X - B
       - (\"escript\":\"foldl\"/\"3\")
-      - (\"abnfc\":\"file\"/\"2\"))",[]}]}.
+      - (\"abnfc\":\"file\"/\"2\")
+      - (\"erlydtl\":\"compile\"/\"3\")
+      - (\"lfe_comp\":\"file\"/\"2\")
+      - (\"neotoma\":\"file\"/\"2\")
+      - (\"protobuffs_compile\":\"scan_file\"/\"1\"))",
+         []}]}.