drm/msm/dpu: fix typo in in sm8550's dma_sblk_5

Fix typo in the name of the sblk structure for the sm8550's dma_sblk_5.

Fixes: efcd0107 ("drm/msm/dpu: add support for SM8550")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/522225/
Link: https://lore.kernel.org/r/20230211231259.1308718-4-dmitry.baryshkov@linaro.org


[quic_abhinavk@quicinc.com: fix minor typo in commit message]
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>