asoc: codecs: bolero: Update mixing path and channel mask for RX path

RX_CDC_DMA_RX0/1/2/3 ports  drives RX0/RX1, RX2/RX3, RX4 and RX5
channels on bolero rx-macro. Update channel mask
as per these mapping and return to channel map
accordingly.

Change-Id: I2e66e601b5137ebc513527827332bbb7cde0acb3
Signed-off-by: Laxminath Kasam <lkasam@codeaurora.org>