When either of the normal or wakeup filter protocols are changed,
refresh the corresponding scancode filter, i.e. try and set the same
scancode filter with the new protocol. If that fails clear the filter
instead.

If no protocol was selected the filter is just cleared, and if no
s_filter callback exists the filter is left unmodified.

Similarly clear the filter mask when the filter is set if no protocol is
currently selected.

This simplifies driver code which no longer has to explicitly worry
about modifying the filter on a protocol change. This also allows the
change_wakeup_protocol callback to be omitted entirely if there is only
a single available wakeup protocol at a time, since selecting no
protocol will automatically clear the wakeup filter, disabling wakeup.
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Reviewed-by: NAntti Seppälä <a.seppala@gmail.com>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>