[media] rc: meson-ir: switch config to NEC decoding on shutdown

On the Amlogic SoCs, the bootloader firmware can handle the IR hardware
in order to Wake up or Power back the system when in suspend on
shutdown mode.

This patch switches the hardware configuration in a state usable by the
firmware to permit powering the system back.

Some vendor bootloader firmware were modified to switch to this
configuration but it may not be the case for all available products.

This patch was originally posted at [1].

[1] https://github.com/LibreELEC/linux-amlogic/pull/27

Signed-off-by: Alex Deryskyba <alex@codesnake.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>