examples/svc_encodeframe.c: rm empty {}s in switch

these have been unnecessary since:
0e97e7049 remove spatial svc experiment

Bug: b/229626362
Change-Id: I57528af4dcb9092b752161c8eaba2e2808c29c5f

examples/svc_encodeframe.c

@@ -552,11 +552,8 @@ vpx_codec_err_t vpx_svc_encode(SvcContext *svc_ctx, vpx_codec_ctx_t *codec_ctx,
   iter = NULL;
   while ((cx_pkt = vpx_codec_get_cx_data(codec_ctx, &iter))) {
     switch (cx_pkt->kind) {
-      case VPX_CODEC_PSNR_PKT: {
-      }
-        ++si->psnr_pkt_received;
-        break;
-      default: { break; }
+      case VPX_CODEC_PSNR_PKT: ++si->psnr_pkt_received; break;
+      default: break;
     }
   }