drm/amd/display: fix the build when DRM_AMD_DC_DCN is not set

Move the new callback outside of the guard.

Fixes: dc55b106 ("drm/amd/display: Disable phantom OTG after enable for plane disable")
CC: Alvin Lee <Alvin.Lee2@amd.com>
CC: Alan Liu <HaoPing.Liu@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/inc/hw/timing_generator.h

@@ -184,8 +184,8 @@ struct timing_generator_funcs {
 	bool (*disable_crtc)(struct timing_generator *tg);
 #ifdef CONFIG_DRM_AMD_DC_DCN
 	void (*phantom_crtc_post_enable)(struct timing_generator *tg);
-	void (*disable_phantom_crtc)(struct timing_generator *tg);
 #endif
+	void (*disable_phantom_crtc)(struct timing_generator *tg);
 	bool (*immediate_disable_crtc)(struct timing_generator *tg);
 	bool (*is_counter_moving)(struct timing_generator *tg);
 	void (*get_position)(struct timing_generator *tg,