ASoC: remove sirf prima/atlas drivers

The CSR SiRF prima2/atlas platforms are getting removed, so this driver
is no longer needed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Barry Song <baohua@kernel.org>
Link: https://lore.kernel.org/r/20210120162553.21666-2-arnd@kernel.org


Signed-off-by: Mark Brown <broonie@kernel.org>