x86: baytrail: fsp: Use a function to update the Azalia config pointer

At present we directly pass the Azalia config pointer to the FSP UPD.
This updates to use a function to do the stuff, like Braswell does.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Stefan Roese <sr@denx.de>