[media] au0828: rework GPIO management for HVR-950q
Restructure the way we bring the various GPIOs out of reset. In particular:
1. we only need to setup the GPIOs as outputs once
2. there's no point in writing 0x40 to register 0x00 since that's the EEPROM
write protect and already it's configured as an input
3. Separate out the act of enabling the power supply and bringing the tuner
and demod out of reset. If you don't then the chip may not be properly
enabled (as the power supply is still ramping up when the chip comes
out of reset). This can result in probing failures.