[amalgam] Fix UCD issue

This actually makes it build now!

Part https://github.com/harfbuzz/harfbuzz/issues/1809

Keeping open to add tests, CI, etc.

src/hb-ucd.cc

@@ -15,6 +15,7 @@
  */
 
 #include "hb.hh"
+#include "hb-unicode.hh"
 #include "hb-machinery.hh"
 
 #include "hb-ucd-table.hh"
@@ -235,10 +236,6 @@ void free_static_ucd_funcs ()
 }
 #endif
 
-extern "C" HB_INTERNAL
-hb_unicode_funcs_t *
-hb_ucd_get_unicode_funcs ();
-
 hb_unicode_funcs_t *
 hb_ucd_get_unicode_funcs ()
 {

src/hb-unicode.cc

@@ -126,8 +126,6 @@ hb_unicode_decompose_compatibility_nil (hb_unicode_funcs_t *ufuncs     HB_UNUSED
 }
 #endif
 
-
-extern "C" hb_unicode_funcs_t *hb_ucd_get_unicode_funcs ();
 extern "C" hb_unicode_funcs_t *hb_glib_get_unicode_funcs ();
 extern "C" hb_unicode_funcs_t *hb_icu_get_unicode_funcs ();
 

src/hb-unicode.hh

@@ -395,4 +395,7 @@ HB_INTERNAL bool
 _hb_unicode_is_emoji_Extended_Pictographic (hb_codepoint_t cp);
 
 
+extern "C" HB_INTERNAL hb_unicode_funcs_t *hb_ucd_get_unicode_funcs ();
+
+
 #endif /* HB_UNICODE_HH */