Fix transmute_copy link

tesuji · Gankra · commit 38b9a76bc8b5 · 2019-08-19T10:04:32.000-04:00
diff --git a/src/transmutes.md b/src/transmutes.md
@@ -36,4 +36,4 @@ pointer casts.
 
 [unbounded lifetime]: unbounded-lifetimes.html
 [transmute]: ../std/mem/fn.transmute.html
-[transmute_copy]: ../std/mem/fn.transmute.html
+[transmute_copy]: ../std/mem/fn.transmute_copy.html
