drm/amd/amdgpu/mmhub_v9_4: Fix naming disparity with 'mmhub_v9_4_set_fault_enable_default()'

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/amd/amdgpu/mmhub_v9_4.c:446: warning: expecting prototype for mmhub_v1_0_set_fault_enable_default(). Prototype was for mmhub_v9_4_set_fault_enable_default() instead

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/mmhub_v9_4.c

@@ -436,7 +436,7 @@ static void mmhub_v9_4_gart_disable(struct amdgpu_device *adev)
 }
 
 /**
- * mmhub_v1_0_set_fault_enable_default - update GART/VM fault handling
+ * mmhub_v9_4_set_fault_enable_default - update GART/VM fault handling
  *
  * @adev: amdgpu_device pointer
  * @value: true redirects VM faults to the default page