Description of problem:
Deploy logging, don't set cpu and memory for fluentd, the default value of requested memory is 736Mi, then set the fluentd requested memory to `500Mi` in the clusterlogging instance, check the fluentd pods, the pods aren't updated, get some error messages in the CLO pod log:
time="2020-03-16T07:01:54Z" level=error msg="Error updating &TypeMeta{Kind:DaemonSet,APIVersion:apps/v1,}: DaemonSet.apps \"fluentd\" is invalid: spec.template.spec.containers[0].resources.requests: Invalid value: \"500Mi\": must be less than or equal to memory limit"
{"level":"error","ts":1584342114.8858852,"logger":"kubebuilder.controller","msg":"Reconciler error","controller":"clusterlogging-controller","request":"openshift-logging/instance","error":"Unable to create or update collection for \"instance\": DaemonSet.apps \"fluentd\" is invalid: spec.template.spec.containers[0].resources.requests: Invalid value: \"500Mi\": must be less than or equal to memory limit","stacktrace":"github.com/go-logr/zapr.(*zapLogger).Error\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/github.com/go-logr/zapr/zapr.go:128\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:217\nsigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func1\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/sigs.k8s.io/controller-runtime/pkg/internal/controller/controller.go:158\nk8s.io/apimachinery/pkg/util/wait.JitterUntil.func1\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/k8s.io/apimachinery/pkg/util/wait/wait.go:133\nk8s.io/apimachinery/pkg/util/wait.JitterUntil\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/k8s.io/apimachinery/pkg/util/wait/wait.go:134\nk8s.io/apimachinery/pkg/util/wait.Until\n\t/go/src/github.com/openshift/cluster-logging-operator/_output/src/k8s.io/apimachinery/pkg/util/wait/wait.go:88"}

Version-Release number of selected component (if applicable):
ose-cluster-logging-operator-v4.4.0-202003130257


How reproducible:
Always

Steps to Reproduce:
1. deploy CLO and EO
2. create clusterlogging instance with https://raw.githubusercontent.com/openshift-qe/v3-testfiles/master/logging/clusterlogging/example.yaml, the default values are:
Containers:
  fluentd:
    Image:      image-registry.openshift-image-registry.svc:5000/openshift/ose-logging-fluentd:v4.4.0
    Port:       24231/TCP
    Host Port:  0/TCP
    Limits:
      memory:  736Mi
    Requests:
      cpu:     100m
      memory:  736Mi

3. add fluentd requested memory to clusterlogging instance

  spec:
    collection:
      logs:
        fluentd:
          resources:
            requests:
              memory: 500Mi
        type: fluentd
4. check the fluentd pod status

Actual results:
The fluentd pods aren't updated

Expected results:
The fluentd pods should be updated to use a smaller memory

Additional info:
If creating clusterlogging instance with resources settings, then change the resource requests, the fluentd pod could be updated.