[m-rev.] diff: avoid ambiguity warnings in compiler

[Julien Fischer]

The following works around problems preventing the compiler from building
when compiled with --intermodule-optimization.

----------------------

Avoid ambiguity warnings in compiler.

compiler/typecheck_errors.m:
     As above.

Julien.

diff --git a/compiler/typecheck_errors.m b/compiler/typecheck_errors.m
index fe8e060..1878b03 100644
--- a/compiler/typecheck_errors.m
+++ b/compiler/typecheck_errors.m
@@ -2607,9 +2607,9 @@ type_to_pieces(MaybeAddQuotes, TVarSet, InstVarSet, ExternalTypeParams,
                  HOPorFStr = pred_or_func_to_full_str(HOPorF),
                  PorFMismatchPieces = [nl,
                      words("The type says this is a"),
-                    words(PorFStr), suffix(","),
+                    words(PorFStr), error_util.suffix(","),
                      words("but its mode says it is a"),
-                    words(HOPorFStr), suffix(".")]
+                    words(HOPorFStr), error_util.suffix(".")]
              ),
              list.length(ArgTypes, NumArgTypes),
              list.length(ArgModes, NumArgModes),
@@ -2636,7 +2636,7 @@ type_to_pieces(MaybeAddQuotes, TVarSet, InstVarSet, ExternalTypeParams,
                      words("The type says this"), words(PorFStr),
                      words("has"), int_fixed(NumArgTypes), words("arguments,"),
                      words("but its mode says it has"),
-                    int_fixed(NumArgModes), suffix(".")]
+                    int_fixed(NumArgModes), error_util.suffix(".")]
              ),
              DetismPieces = [words("is"), words(determinism_to_string(Detism))]
          ),
@@ -2647,7 +2647,7 @@ type_to_pieces(MaybeAddQuotes, TVarSet, InstVarSet, ExternalTypeParams,
                  ArgBlockPieces = []
              ;
                  ArgPieces = [_ | _],
-                ArgBlockPieces = [suffix("("), nl_indent_delta(1)] ++
+                ArgBlockPieces = [error_util.suffix("("), nl_indent_delta(1)] ++
                      component_list_to_line_pieces(ArgPieces, []) ++
                      [nl_indent_delta(-1), fixed(")")]
              )