serial: kgdboc: Fix bad line wrapping in comment

In commit a4912303 ("serial: kgdboc: Allow earlycon initialization
to be deferred") it looks like Daniel really took Linus's new
suggestion about not needing to wrap at 80 columns to heart and he
jammed two full lines of comments into one line.  Either that or he
just somehow accidentally deleted a carriage return when doing final
edits on the patch.  In either case let's make it look prettier.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200602124044.1.Iee31247bc080d42a02e167454b1225a1b4283705@changeid


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>