lib/icu/Canonicalize: convert all punctuation to ASCII

To make tag matching easier.

Closes https://github.com/MusicPlayerDaemon/MPD/issues/1669

src/lib/icu/Canonicalize.hxx

@@ -28,6 +28,15 @@
 
 class AllocatedString;
 
+/**
+ * Throws on error.
+ */
+void
+IcuCanonicalizeInit();
+
+void
+IcuCanonicalizeFinish() noexcept;
+
 /**
  * Transform the given string to "canonical" form to allow fuzzy
  * string comparisons.  The full set of features (if ICU is being