dt-bindings: soc: samsung: usi: add USIv1 and samsung,exynos8895-usi

dt-bindings: soc: samsung: usi: add USIv1 and samsung,exynos8895-usi

Add new constants for choosing the additional USIv1 configuration modes
in device tree. Those are further used in the USI driver to figure out
which value to write into SW_CONF register. Modify the current USI IP-core
bindings to include information about USIv1 and a compatible for
exynos8895.

In the original bindings commit, protocol mode definitions were named
with the version of the supported USI (in this case, V2) with the idea of
leaving enough room in the future for other versions of this block. This,
however, is not how the modes should be modelled. The modes are not
version specific and you should not be able to tell USI which version of
a mode to use - that has to be handled in the driver - thus encoding this
information in the binding is meaningless. Only one constant per mode is
needed, so while we're at it, add new constants with the prefix USI_MODE
and mark the old ones as depracated.

Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250204172803.3425496-2-ivo.ivanov.ivanov1@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>