Config load error handling doesn't mention the file path

[christopherhein]

go run ./main.go
2020-11-06T20:54:59.837-0800    ERROR   setup   unable to load the config file  {"error": "file could not be read from filesystem"}
github.com/go-logr/zapr.(*zapLogger).Error
        /Users/chris/Code/pkg/mod/github.com/go-logr/zapr@v0.2.0/zapr.go:132
main.main
        /Users/chris/Code/src/sigs.k8s.io/kubebuilder/sample/main.go:61
runtime.main
        /usr/local/Cellar/go/1.15.2/libexec/src/runtime/proc.go:204
exit status 1
make: *** [run] Error 1

https://github.com/kubernetes-sigs/controller-runtime/blob/master/pkg/config/config.go#L101

Ref #895