add minimal reservations for kube2iam as per: https://github.com/helm/charts/blob/master/stable/kube2iam/values.yaml\#L76-L82

Branched off from an older commit as Paul is on holiday and hischanges
in master want to change servicemounting on cronofy. For now, Ill evert
back to this commit that I know doesn't want to change anything.
Signed-off-by: Danny <danny@Dannys-MacBook-Pro.local>