drm/msm/a6xx: fix frequency not always being restored on GMU resume

The patch reorganizing the set_freq function made it so the gmu resume
doesn't always set the frequency, because a6xx_gmu_set_freq() exits early
when the frequency hasn't been changed. Note this always happens when
resuming GMU after recovering from a hang.

Use a simple workaround to prevent this from happening.

Fixes: 1f60d114 ("drm: msm: a6xx: send opp instead of a frequency")
Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drivers/gpu/drm/msm/adreno/a6xx_gmu.c

@@ -851,6 +851,7 @@ static void a6xx_gmu_set_initial_freq(struct msm_gpu *gpu, struct a6xx_gmu *gmu)
 	if (IS_ERR_OR_NULL(gpu_opp))
 		return;
 
+	gmu->freq = 0; /* so a6xx_gmu_set_freq() doesn't exit early */
 	a6xx_gmu_set_freq(gpu, gpu_opp);
 	dev_pm_opp_put(gpu_opp);
 }