dt-bindings: arm: qcom: Add Fxtec Pro1X

Document F(x)tec Pro1X as a SM6115 device.

Signed-off-by: Dang Huynh <danct12@riseup.net>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230505-fxtec-pro1x-support-v3-1-0c9c7f58b205@riseup.net