Change in coreboot[master]: mb/pcengines/apu2/Kconfig: Remove APU2_PINMUX_OFF_X

[Michał Żygowski (Code Review)]

Attention is currently required from: Frans Hendriks, Piotr Król.
Michał Żygowski has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49972 )

Change subject: mb/pcengines/apu2/Kconfig: Remove APU2_PINMUX_OFF_X
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Patch Set 1:

(1 comment)

Patchset:

PS1: 
They are actually used indirectly. See https://review.coreboot.org/cgit/coreboot.git/tree/src/mainboard/pcengines/a...

So when the PINMUX_OFF is selected, neither GPIO nor UART is enabled, so it is an equivalent of "DO NOTHING". If we are to remove it, there must be an equivalent in the code.