Fix minor typo

Author: gosharplite

docs/book/src/reference/generating-crd.md

@@ -181,7 +181,7 @@ controller-gen, using the same syntax as markers.  For instance, to
 generate CRDs with "trivial versions" (no version conversion webhooks), we
 call `controller-gen crd:trivialVersions=true paths=./api/...`.
 
-controller-gen also supports different output "rules" to controller how
+controller-gen also supports different output "rules" to control how
 and where output goes.  Notice the `manifests` make rule (condensed
 slightly to only generate CRDs):