arm64: dts: qcom: split beryllium dts into common dtsi and tianma dts

There are two panel variants of Xiaomi Poco F1. Tianma and EBBG panel.
The previous beryllium dts supported the Tianma variant. In order to
add support for EBBG variant, the common nodes from beryllium dts are
moved to a new common dtsi and to make the variants distinguishable,
sdm845-xiaomi-beryllium.dts is now named as
sdm845-xiaomi-beryllium-tianma.dts. The model property is updated to
distinguish between the variants. The compatibility property is
moved to the tianma variant, but it is not updated to avoid any
further conflict with other projects/users that might depend on it.

Signed-off-by: Joel Selvaraj <joelselvaraj.oss@gmail.com>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Caleb Connolly <caleb@connolly.tech>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220909035447.36674-2-joelselvaraj.oss@gmail.com