update sys.reflect and sys.unreflect to accomodate
the possibility of large objects in interface values.

R=r
DELTA=171  (97 added, 22 deleted, 52 changed)
OCL=22382
CL=22382
diff --git a/src/runtime/runtime.h b/src/runtime/runtime.h
index 687e4e0..ba210ae 100644
--- a/src/runtime/runtime.h
+++ b/src/runtime/runtime.h
@@ -110,7 +110,7 @@
 struct Iface
 {
 	Itype *type;
-	void *data[1];	// could make bigger later, but must be in sync with compilers
+	void *data;
 };
 
 struct	Array