drm/msm/dpu: fix x1e80100 intf_6 underrun/vsync interrupt

The IRQ indexes for the intf_6 underrun/vsync interrupts are swapped.
DPU_IRQ_IDX(MDP_SSPP_TOP0_INTR, 16) is the actual underrun interrupt and
DPU_IRQ_IDX(MDP_SSPP_TOP0_INTR, 17) is the vsync interrupt.

This causes timeout errors when using the DP2 controller, e.g.
  [dpu error]enc37 frame done timeout
  *ERROR* irq timeout id=37, intf_mode=INTF_MODE_VIDEO intf=6 wb=-1, pp=2, intr=0
  *ERROR* wait disable failed: id:37 intf:6 ret:-110

Correct them to fix these errors and make DP2 work properly.

Cc: stable@vger.kernel.org
Fixes: e3b1f369 ("drm/msm/dpu: Add X1E80100 support")
Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/624681/
Link: https://lore.kernel.org/r/20241115-x1e80100-dp2-fix-v1-1-727b9fe6f390@linaro.org


Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>