arm64: dts: qcom: msm8916-samsung-gt58: Enable the touchkeys

The tablet has two capacitive buttons on the scren bezel. Enable them by
adding the keycodes in the dt.

Signed-off-by: Nikita Travkin <nikita@trvn.ru>
Link: https://lore.kernel.org/r/20240806-msm8916-gt58-tkey-v1-1-8987b06c5921@trvn.ru


Signed-off-by: Bjorn Andersson <andersson@kernel.org>