drm/msm/mdss: Fix spelling mistake "Unuspported" -> "Unsupported"

There is a spelling mistake in a dev_error message. Fix it.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/529400/
Link: https://lore.kernel.org/r/20230329093026.418847-1-colin.i.king@gmail.com


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>