Disable CGO when running generate deep copy

This should fix the job that periodically builds images, since the
container where the releas staging target is run doesn't have gcc
installed.

Author: g-gaston

Makefile

@@ -149,7 +149,7 @@ DEEPCOPY_GEN_INPUTS=$(shell find ./api -name "*test*" -prune -o -name "*zz_gener
 .PHONY: generate-deepcopy
 generate-deepcopy: $(DEEPCOPY_GEN_TARGETS) ## Generate code containing DeepCopy, DeepCopyInto, and DeepCopyObject method implementations.
 api/%/zz_generated.deepcopy.go: $(CONTROLLER_GEN) $(DEEPCOPY_GEN_INPUTS)
-	$(CONTROLLER_GEN) object:headerFile="hack/boilerplate.go.txt" paths="./..."
+	CGO_ENABLED=0 $(CONTROLLER_GEN) object:headerFile="hack/boilerplate.go.txt" paths="./..."
 
 MANIFEST_GEN_INPUTS=$(shell find ./api ./controllers -type f -name "*test*" -prune -o -name "*zz_generated*" -prune -o -print)
 # Using a flag file here as config output is too complicated to be a target.