Sensible defaulting for Azure VMs with security type TrustedLaunch

[dharapvj]

This is a follow-up ticket on #2013

The fix done via PR #2020 needs us to write additional values mandatorily

securityProfile:
  securityType: TrustedLaunch
  secureBootEnabled: true
  vTpmEnabled: true

Can we make it easier by just specifying securityType: TrustedLaunch and then defaulting rest of the two params when securityType is TrustedLaunch?

Those sub params can continue to exist for someone who wants to override them manually.. but if user does not specify it, then they should be default to above values in case securityType is TrustedLaunch