Don't check in generated deep-copy code

This mostly takes the previously checked in files and removes them, and moves
the generation to be on-demand instead of manual.  Manually verified no change
in generated output.

hack/update-codegen.sh

@@ -26,14 +26,12 @@ kube::golang::setup_env
 BUILD_TARGETS=(
   cmd/libs/go2idl/client-gen
   cmd/libs/go2idl/conversion-gen
-  cmd/libs/go2idl/deepcopy-gen
   cmd/libs/go2idl/set-gen
 )
 make -C "${KUBE_ROOT}" WHAT="${BUILD_TARGETS[*]}"
 
 clientgen=$(kube::util::find-binary "client-gen")
 conversiongen=$(kube::util::find-binary "conversion-gen")
-deepcopygen=$(kube::util::find-binary "deepcopy-gen")
 setgen=$(kube::util::find-binary "set-gen")
 
 # Please do not add any logic to this shell script. Add logic to the go code
@@ -67,18 +65,6 @@ ALL_K8S_TAG_FILES=$(
             | sed 's|^./||'
         )
     )
-DEEP_COPY_DIRS=$(
-    grep -l '+k8s:deepcopy-gen=' ${ALL_K8S_TAG_FILES} \
-        | xargs dirname \
-        | sort -u
-    )
-DEEPCOPY_INPUTS=$(
-    for d in ${DEEP_COPY_DIRS}; do
-        echo k8s.io/kubernetes/$d
-    done | paste -sd,
-    )
-${deepcopygen} -i ${DEEPCOPY_INPUTS}
-
 CONVERSION_DIRS=$(
     grep '^// *+k8s:conversion-gen=' ${ALL_K8S_TAG_FILES} \
         | cut -f1 -d:                                     \