Integrate linux-imx-kuk/fix_wm9705_dig2

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Commit: seco-ne/kernel/linux-imx-kuk@b5006e3e

driver:wm9705: Check and re-set dig2 config register

Due to an unknown reason, the dig2 config register resets randomly. This
disables the generation of pen-down interrupts. Without the interrupt, doesn't
sample further touches.
As a first workaround, we check the dig2 config register before exiting the
sample function and re-set the config value, if it was reset.

BCS 746-001452
BCS 746-001447