onclite: doze: Get rid of HelpDialogFragment class

As preparation to upgrade the sdk get rid of this private class.
Fragments must be a public static class to be properly recreated from instance state.

Also change the behaviour to only hide the dialog when confirmed instead of also when it is cancelled.

Change-Id: I171aa2345058edae7520c37942c3c11b3cdfdfdc
Signed-off-by: Hadad <hadad@linuxmail.org>