Change in coreboot[master]: Unify all Lenovo t520 variants

[Peter Lemenkov (Code Review)]

Peter Lemenkov has posted comments on this change. ( https://review.coreboot.org/28936 )

Change subject: Unify all Lenovo t520 variants
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Patch Set 2:
> Build Failed
>
> https://qa.coreboot.org/job/coreboot-gerrit/80240/ : FAILURE
>
> https://qa.coreboot.org/job/coreboot-checkpatch/33914/ : SUCCESS

Not sure if I understand it correctly:

#!!!!! Error: #if CONFIG_BOARD_LENOVO_T520 used at src/mainboard/lenovo/t520/smihandler.c:36.  IS_ENABLED should be used for type 'bool'
#!!!!! Error: #if CONFIG_BOARD_LENOVO_T520 used at src/mainboard/lenovo/t520/smihandler.c:46.  IS_ENABLED should be used for type 'bool'
# 2 errors

Isn't this actually a proper declaration of a bool variable?

config BOARD_LENOVO_L520
        bool "ThinkPad L520"
        select BOARD_LENOVO_BASEBOARD_T520