[coreboot-gerrit] Change in coreboot[master]: lib: Add config MAINBOARD_OPTIONS for getting options from mainboard

[Johnny Lin (Code Review)]

Johnny Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/45134 )

Change subject: lib: Add config MAINBOARD_OPTIONS for getting options from mainboard
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Patch Set 12:

(1 comment)

https://review.coreboot.org/c/coreboot/+/45134/12/src/include/option.h 
File src/include/option.h:

https://review.coreboot.org/c/coreboot/+/45134/12/src/include/option.h@25 
PS12, Line 25: mainboard_get_option
> I guess I don't completely understand what the mainboard_get_option is supposed to be. […]

The purpose of the change was to integrate getting debug log level from a mainboard defined function with get_option() API, so a generic mainboard_get_option() was added in get_option(). But if it makes more sense to make it specific to the method of getting the option, I can revert mainboard_get_option and only focus on the console log level part. Something like below: 
console/init.c
static void init_log_level(void)
{
    int debug_level = CONFIG_DEFAULT_CONSOLE_LOGLEVEL;
        if(CONFIG(CONSOLE_OVERRIDE_LOGLEVEL))
                debug_level = get_console_loglevel();
        else
            get_option(&debug_level, "debug_level");

set_log_level(debug_level);
}
To limit the scope of this change I am leaning toward this direction, to integrate into get_option requires more discussion.