re-reading broken on time control function

It seems that any functionObject with an executeControl or writeControl will not properly re-read for its managed functionObject when modified.

Need to change timeControl::read(const dictionary&) to include this. Eg,

writeControl_.read(dict);
executeControl_.read(dict);
readControls();

// Missing this:
foPtr_->read();

Versions affected: 1712, 1706, 1612

@andy @sbna