soc/intel/apollolake: Clean up UART code

Clean up and move UART related code under a single uart.c file.

Change-Id: I9a30258ba43ee5920f585c1bd06bc25773778ec4
Signed-off-by: Aamir Bohra <aamir.bohra@intel.com>
Reviewed-on: https://review.coreboot.org/22754
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
3 files changed