nvidia: fix sparse warnings

Fix this sparse warnings:

  drivers/video/nvidia/nv_accel.c:304:3: warning: returning void-valued expression
  drivers/video/nvidia/nv_accel.c:323:3: warning: returning void-valued expression
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/video/nvidia/nv_accel.c

@@ -300,8 +300,10 @@ void nvidiafb_copyarea(struct fb_info *info, const struct fb_copyarea *region)
 	if (info->state != FBINFO_STATE_RUNNING)
 		return;
 
-	if (par->lockup)
-		return cfb_copyarea(info, region);
+	if (par->lockup) {
+		cfb_copyarea(info, region);
+		return;
+	}
 
 	NVDmaStart(info, par, BLIT_POINT_SRC, 3);
 	NVDmaNext(par, (region->sy << 16) | region->sx);
@@ -319,8 +321,10 @@ void nvidiafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
 	if (info->state != FBINFO_STATE_RUNNING)
 		return;
 
-	if (par->lockup)
-		return cfb_fillrect(info, rect);
+	if (par->lockup) {
+		cfb_fillrect(info, rect);
+		return;
+	}
 
 	if (info->var.bits_per_pixel == 8)
 		color = rect->color;