drm/amd/display: make amdgpu_dm_irq_handler static

It's not used outside the file.
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.c

@@ -560,9 +560,9 @@ static void amdgpu_dm_irq_immediate_work(struct amdgpu_device *adev,
  * Generic IRQ handler, calls all registered high irq work immediately, and
  * schedules work for low irq
  */
-int amdgpu_dm_irq_handler(struct amdgpu_device *adev,
-			  struct amdgpu_irq_src *source,
-			  struct amdgpu_iv_entry *entry)
+static int amdgpu_dm_irq_handler(struct amdgpu_device *adev,
+				 struct amdgpu_irq_src *source,
+				 struct amdgpu_iv_entry *entry)
 {
 
 	enum dc_irq_source src =

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_irq.h

@@ -80,15 +80,6 @@ void amdgpu_dm_irq_unregister_interrupt(struct amdgpu_device *adev,
 					enum dc_irq_source irq_source,
 					void *ih_index);
 
-/**
- * amdgpu_dm_irq_handler
- * Generic IRQ handler, calls all registered high irq work immediately, and
- * schedules work for low irq
- */
-int amdgpu_dm_irq_handler(struct amdgpu_device *adev,
-			  struct amdgpu_irq_src *source,
-			  struct amdgpu_iv_entry *entry);
-
 void amdgpu_dm_set_irq_funcs(struct amdgpu_device *adev);
 
 void amdgpu_dm_hpd_init(struct amdgpu_device *adev);