dt-bindings: pinctrl: samsung: Add pin drive definitions for Exynos850

All Exynos850 GPIO blocks can use EXYNOS5420_PIN_DRV* definitions,
except GPIO_HSI block. Add pin drive strength definitions for GPIO_HSI
block correspondingly.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211217161549.24836-6-semen.protsenko@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>