drm/amdgpu: return 0 by default in amdgpu_pm_load_smu_firmware

Fixes SI cards running on amdgpu.

Fixes: 1929059893022 ("drm/amd/amdgpu: add RLC firmware to support raven1 refresh")
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=110883
Reviewed-by: Evan Quan <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 
 int amdgpu_pm_load_smu_firmware(struct amdgpu_device *adev, uint32_t *smu_version)
 {
-	int r = -EINVAL;
+	int r;
 
 	if (adev->powerplay.pp_funcs && adev->powerplay.pp_funcs->load_firmware) {
 		r = adev->powerplay.pp_funcs->load_firmware(adev->powerplay.pp_handle);
···
 		}
 		*smu_version = adev->pm.fw_version;
 	}
-	return r;
+	return 0;
 }
 
 int amdgpu_pm_sysfs_init(struct amdgpu_device *adev)