drivers/pc80/mc146818rtc: Reduce superfluous preprocessor use

cmos_init() had layers of preprocessor directives, which resulted in
a complete mess. Refactor it to make use of the IS_ENABLED() macro.
This improves readability significantly.

One of the changes is to remove in inline stub declaration of
(get|set)_option. Although that provided the ability for the compiler
to optimize out code when USE_OPTION_TABLE is not selected, there is
no evidence that such savings are measureable.

Change-Id: I07f00084d809adbb55031b2079f71136ade3028e
Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-on: http://review.coreboot.org/8306
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

0 files changed, 0 insertions, 0 deletions