fellow_cache: fix off by one in fellow_cache_seglist_init

src/fellow_cache.c

@@ -1719,7 +1719,7 @@ fellow_cache_seglist_init(void *ptr, size_t space, struct fellow_cache_obj *fco)
 
 	AN(ptr);
 	assert(PAOK(ptr));
-	assert(space > sizeof *fcsl);
+	assert(space >= sizeof *fcsl);
 	INIT_OBJ(fcsl, FELLOW_CACHE_SEGLIST_MAGIC);
 	lsegs = space / sizeof *fcsl->segs;
 	assert(lsegs <= UINT16_MAX);