nix,vere: move ivory def to its own source file

nix/pkgs/pill/ivory.nix

@@ -34,7 +34,7 @@ in {
 
       mkdir -p $out/include
       cat $src > $file
-      xxd -i $file > $out/include/ivory.h
+      xxd -i $file > $out/include/ivory_impl.h
     '';
 
     preferLocalBuild = true;

pkg/urbit/include/ur/ivory.h

@@ -0,0 +1,7 @@
+#ifndef UR_IVORY_H
+#define UR_IVORY_H
+
+extern unsigned char u3_Ivory_pill[];
+extern unsigned int u3_Ivory_pill_len;
+
+#endif

pkg/urbit/include/ur/ur.h

@@ -4,6 +4,7 @@
 #include "ur/defs.h"
 #include "ur/bitstream.h"
 #include "ur/hashcons.h"
+#include "ur/ivory.h"
 #include "ur/serial.h"
 
 #endif /* ifndef UR_H */

pkg/urbit/tests/boot_tests.c

@@ -2,14 +2,6 @@
 #include "vere/vere.h"
 #include "ur/ur.h"
 
-//  XX ivory.h just declares these; if it's included elsewhere
-//  (currently king.c), this will cause duplicate definition
-//  errors. so we just extern them instead.
-//
-extern unsigned char u3_Ivory_pill[];
-extern unsigned int u3_Ivory_pill_len;
-//  #include "ivory.h"
-
 /* _setup(): prepare for tests.
 */
 static void

pkg/urbit/ur/ivory.c

@@ -0,0 +1,3 @@
+#include "ur/ivory.h"
+
+#include "ivory_impl.h"

pkg/urbit/vere/king.c

@@ -8,8 +8,6 @@
 #include <curl/curl.h>
 #include <uv.h>
 
-#include "ivory.h"
-
 //  stash config flags for worker
 //
 static c3_w sag_w;