[Why]
During gpu-reset, we toggle vblank irq by calling dc_interrupt_set()
instead of amdgpu_irq_get/put() because we don't want to change the irq
source's refcount. However, we see the warning when vblank irq is enabled
by dc_interrupt_set() during gpu-reset but disabled by amdgpu_irq_put()
after gpu-reset.

[How]
Only in dm_gpureset_toggle_interrupts() we toggle vblank interrupts by
calling dc_interrupt_set(). Apart from this we call dm_set_vblank()
which uses amdgpu_irq_get/put() to operate vblank irq.

Reviewed-by: Bhawanpreet Lakha <bhawanpreet.lakha@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Alan Liu <haoping.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>