drm/amdgpu: fix out of bounds access in gfx11 during ip dump

During ip dump in gfx11 the index variable is reused but is
not reinitialized to 0 and this causes the index calculation
to be wrong and access out of bound access.

Acked-by: Christian König <[e-mail]>
Signed-off-by: Sunil Khatri <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/gfx_v11_0.c

···
 	if (!adev->gfx.ip_dump_gfx_queues)
 		return;
 
+	index = 0;
 	reg_count = ARRAY_SIZE(gc_gfx_queue_reg_list_11);
 	drm_printf(p, "\nnum_me: %d num_pipe: %d num_queue: %d\n",
 		   adev->gfx.me.num_me,
···
 	if (!adev->gfx.ip_dump_gfx_queues)
 		return;
 
+	index = 0;
 	reg_count = ARRAY_SIZE(gc_gfx_queue_reg_list_11);
 	amdgpu_gfx_off_ctrl(adev, false);
 	mutex_lock(&adev->srbm_mutex);