ARM: OMAP: Define AUDIO_MCBSP_DATAREAD/WRITE for OMAP16xx as well

Fix error

sound/oss/omap-audio-dma-intfc.c:715: error: `AUDIO_MCBSP_DATAWRITE'
undeclared (first use in this function)
sound/oss/omap-audio-dma-intfc.c:745: error: `AUDIO_MCBSP_DATAREAD'
undeclared (first use in this function)

Signed-off-by: Dirk Behme <dirk.behme_at_de.bosch.com>