[PATCH] mmc: rockchip_sdhci: Do not test unsigned for being less than 0

[Peng Fan]

On Thu, Jul 31, 2025 at 12:46:10PM +0100, Andrew Goodbody wrote:
>In rockchip_sdhci_execute_tuning the variable tuning_loop_counter is
>tested for being less than 0. Ensure that it is a signed type by
>declaring it as s8 instead of char.
>
>This issue was found by Smatch.
>
>Signed-off-by: Andrew Goodbody <andrew.goodbody at linaro.org>

Reviewed-by: Peng Fan <peng.fan at nxp.com>