ASoC: s3c24xx-i2s: pass DMA channels as platform data

This is a minor cleanup to make the s3c2412-i2s and s3c24xx-i2s
drivers independent of the mach/dma.h header file and to allow
removing the dependency on the specific dmaengine driver in the
next patch.

As a side not, only the s3c24xx-i2s driver seems to still be
used, while the definition of the s3c2412-i2s platform device was
removed in commit 6d259a25 ("ARM: SAMSUNG: use static
declaration when it is not used in other files") after it had
never been referenced since its introduction in f0fba2ad


("ASoC: multi-component - ASoC Multi-Component Support").

Apparently it should have been used by mach-jive.c, but that
never happened. My patch at this point leaves the current state
unchanged, we can decide whether to fix or delete the jive
driver and s3c2412-i2s another time.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>