Remove more cruft leftover from nb_coerce.  Rename nb_coerce to
nb_reserved.
diff --git a/Objects/setobject.c b/Objects/setobject.c
index 079f404..ba7d2c4 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -1881,7 +1881,7 @@
 	(binaryfunc)set_and,		/*nb_and*/
 	(binaryfunc)set_xor,		/*nb_xor*/
 	(binaryfunc)set_or,		/*nb_or*/
-	0,				/*nb_coerce*/
+	0,				/*nb_reserved*/
 	0,				/*nb_int*/
 	0,				/*nb_long*/
 	0,				/*nb_float*/