Automatic merge from submit-queue (batch tested with PRs 49850, 47782, 50595, 50730, 51341)
fix ReadOnlyPort defaulting, CAdvisorPort documentation
The ReadOnlyPort defaulting prevented passing 0 to diable via
the KubeletConfiguraiton struct.
The HealthzPort defaulting prevented passing 0 to disable via the
KubeletConfiguration struct. The documentation also failed to mention
this, but the check is performed in code.
The CAdvisorPort documentation failed to mention that you can pass 0 to
disable.
fixes#51345