usb: typec: tps6598x: Add debugfs entries for customer use word

This allows to verify that a sane firmware is on the device.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
2 jobs for usb-c-current in 39 minutes and 12 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
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passed #318844
librem5
build:aarch64

00:14:54

canceled #318845
librem5:arm64
build:deb

00:39:12