Change in coreboot[master]: soc/medaitek: add prompt string to config MTK_DFD

[Hung-Te Lin (Code Review)]

Attention is currently required from: Rex-BC Chen.
Hung-Te Lin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/59621 )

Change subject: soc/medaitek: add prompt string to config MTK_DFD
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Patch Set 5:

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/59621/comment/6881fa65_810e2f9c 
PS5, Line 9: enable MTK_DFD by overlay
allow selecting MTK_DFD manually.

https://review.coreboot.org/c/coreboot/+/59621/comment/45e656b0_b4b7fdbd 
PS5, Line 11: enable MTK_DFD
Select and enable MTK_DFD then successfully built firmware images.

File src/soc/mediatek/common/Kconfig:

https://review.coreboot.org/c/coreboot/+/59621/comment/3890c185_44168e5b 
PS5, Line 40: default n
since we're here, 'default n' is not needed unless if you'll override it in some Kconfig files.