drm/nouveau/disp: remove unused function in sorg94.c

We get 1 warning when building kernel with W=1:
drivers/gpu/drm/nouveau/nvkm/engine/disp/sorg94.c:49:1: warning: no previous prototype for 'g94_sor_output_new' [-Wmissing-prototypes]

In fact, this function is called by no one and not exported,
so this patch removes it.
Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/engine/disp/sorg94.c

@@ -45,14 +45,6 @@ static const struct nvkm_output_func
 g94_sor_output_func = {
 };
 
-int
-g94_sor_output_new(struct nvkm_disp *disp, int index,
-		   struct dcb_output *dcbE, struct nvkm_output **poutp)
-{
-	return nvkm_output_new_(&g94_sor_output_func, disp,
-				index, dcbE, poutp);
-}
-
 /*******************************************************************************
  * DisplayPort
  ******************************************************************************/