The aq_mode should be off if lossless mode

With lossless mode, don't change the quantizers.

BUG=aomedia:1196

Change-Id: I1499e6582bfdc9eeac59703c229eb968757ba29a

av1/av1_cx_iface.c

diff --git a/av1/av1_cx_iface.c b/av1/av1_cx_iface.c
index ce1c739..1bdeceb 100644
--- a/av1/av1_cx_iface.c
+++ b/av1/av1_cx_iface.c
@@ -408,13 +408,20 @@
   RANGE_CHECK(extra_cfg, color_range, 0, 1);
 
 #if CONFIG_DIST_8X8
-  if (extra_cfg->enable_dist_8x8 && extra_cfg->lossless)
-    ERROR("dist-8x8 cannot be used with lossless compression.");
   RANGE_CHECK(extra_cfg, tuning, AOM_TUNE_PSNR, AOM_TUNE_DAALA_DIST);
 #else
   RANGE_CHECK(extra_cfg, tuning, AOM_TUNE_PSNR, AOM_TUNE_SSIM);
 #endif
 
+  if (extra_cfg->lossless) {
+    if (extra_cfg->aq_mode != 0)
+      ERROR("Only --aq_mode=0 can be used with --lossless=1.");
+#if CONFIG_DIST_8X8
+    if (extra_cfg->enable_dist_8x8)
+      ERROR("dist-8x8 cannot be used with lossless compression.");
+#endif
+  }
+
   return AOM_CODEC_OK;
 }