aomenc: add an option to disable loop-restoration

This mirrors the behavior of the corresponding option for CDEF.

Change-Id: Ifbdacb1bedbde2fa740086593384567a2f44b342
diff --git a/av1/encoder/encoder.c b/av1/encoder/encoder.c
index a45916c..6f96616 100644
--- a/av1/encoder/encoder.c
+++ b/av1/encoder/encoder.c
@@ -5163,7 +5163,7 @@
   struct loopfilter *lf = &cm->lf;
   int no_loopfilter = 0;
 #if CONFIG_LOOP_RESTORATION
-  int no_restoration = 0;
+  int no_restoration = !cpi->oxcf.using_restoration;
 #endif  // CONFIG_LOOP_RESTORATION
 
   if (is_lossless_requested(&cpi->oxcf)