Remove generated file rules in make

This is all covered by update-codegen.sh now.

The old `make generated_files` rule still exists, but just prints a
warning.

hack/jenkins/test-dockerized.sh

@@ -47,7 +47,6 @@ export LOG_LEVEL=4
 
 cd "${GOPATH}/src/k8s.io/kubernetes"
 
-make generated_files
 go install ./cmd/...
 ./hack/install-etcd.sh
 

hack/make-rules/update.sh

@@ -22,14 +22,6 @@ set -o pipefail
 KUBE_ROOT=$(dirname "${BASH_SOURCE[0]}")/../..
 source "${KUBE_ROOT}/hack/lib/init.sh"
 
-# If called directly, exit.
-if [[ "${CALLED_FROM_MAIN_MAKEFILE:-""}" == "" ]]; then
-    echo "ERROR: $0 should not be run directly." >&2
-    echo >&2
-    echo "Please run this command using \"make update\""
-    exit 1
-fi
-
 SILENT=${SILENT:-true}
 ALL=${FORCE_ALL:-false}
 

hack/make-rules/vet.sh

@@ -23,14 +23,6 @@ source "${KUBE_ROOT}/hack/lib/init.sh"
 
 cd "${KUBE_ROOT}"
 
-# If called directly, exit.
-if [[ "${CALLED_FROM_MAIN_MAKEFILE:-""}" == "" ]]; then
-    echo "ERROR: $0 should not be run directly." >&2
-    echo >&2
-    echo "Please run this command using \"make vet\""
-    exit 1
-fi
-
 # Filter out arguments that start with "-" and move them to goflags.
 targets=()
 for arg; do

hack/verify-typecheck.sh

@@ -28,8 +28,6 @@ kube::golang::verify_go_version
 
 cd "${KUBE_ROOT}"
 
-make --no-print-directory -C "${KUBE_ROOT}" generated_files
-
 # As of June, 2020 the typecheck tool is written in terms of go/packages, but
 # that library doesn't work well with multiple modules.  Until that is done,
 # force this tooling to run in a fake GOPATH.