Don't set .read_flag_mask for adav803, it's for adav801 only.

Fixes: 0c2d6964 ("ASoC: adav80x: Split SPI and I2C code into different modules")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org