drm/msm/dpu: guard ctl irq callback register/unregister

CTLs on older qualcomm SOCs like msm8953 and msm8996 has not got interrupts,
so better to skip CTL irq callback register/unregister
make dpu_ctl_cfg be able to define without intr_start.
Signed-off-by: Barnabás Czémán <trabarni@gmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/596854/
Link: https://lore.kernel.org/r/20240509-ctl_irq-v1-1-9433f2da9dc7@gmail.comSigned-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c

@@ -307,7 +307,7 @@ static void dpu_encoder_phys_cmd_irq_enable(struct dpu_encoder_phys *phys_enc)
 				       phys_enc);
 	dpu_encoder_phys_cmd_control_vblank_irq(phys_enc, true);
 
-	if (dpu_encoder_phys_cmd_is_master(phys_enc))
+	if (dpu_encoder_phys_cmd_is_master(phys_enc) && phys_enc->irq[INTR_IDX_CTL_START])
 		dpu_core_irq_register_callback(phys_enc->dpu_kms,
 					       phys_enc->irq[INTR_IDX_CTL_START],
 					       dpu_encoder_phys_cmd_ctl_start_irq,
@@ -320,7 +320,7 @@ static void dpu_encoder_phys_cmd_irq_disable(struct dpu_encoder_phys *phys_enc)
 					   phys_enc->hw_pp->idx - PINGPONG_0,
 					   phys_enc->vblank_refcount);
 
-	if (dpu_encoder_phys_cmd_is_master(phys_enc))
+	if (dpu_encoder_phys_cmd_is_master(phys_enc) && phys_enc->irq[INTR_IDX_CTL_START])
 		dpu_core_irq_unregister_callback(phys_enc->dpu_kms,
 						 phys_enc->irq[INTR_IDX_CTL_START]);