ril: power-cycle modem and give some more time

 * This helps to get the modem up and running reliably

Signed-off-by: Lukas Märdian <lukas@goldelico.com>
ril: GTA04a3: don't power-on/off the modem, it's always on

Signed-off-by: Lukas Märdian <lukas@goldelico.com>