ASoC: uda134x: Optionally initialize L3 ops to default GPIO ops

The GPIO ops can be selected by platform_data which allows the
codec platform device to probe without the sound card's driver
intervention.

The downside is that it will request GPIOs on behalf of the codec
device and thus allow only one user on the bus, but it desn't seem
to be a limitation with current code and usage of the GPIO ops is
optional anyway.
The proper approach would presumably be to create a proper Linux
bus driver for L3, should this rather ancient bus specification
suddenly gain more interest.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>