Fix two bugs with bold and italic labels when a non-Base config layer is
active.
First, when constructing a ConfigControl the label wouldn't be
bolded until the next time a ConfigChanged signal was received. This
would happen if the user started a game before opening a config window
for the first time since starting Dolphin.
Second, ConfigRadioInt would bold/italicize every radio button for that
setting instead of just the selected radio button.
Renames the IsConfigLocal function to ShouldLabelBeBold, since the
former name was inaccurate if m_layer wasn't the local layer.