rtc: Change default scaler filter to SMOOTH for RTC

Fixes assert in resize test.

BUG=aomedia:2735

Change-Id: I356f94393f4eef1b8d8098e53db91916d6c31c29
diff --git a/av1/encoder/encoder.c b/av1/encoder/encoder.c
index 328faeb..cc6dd30 100644
--- a/av1/encoder/encoder.c
+++ b/av1/encoder/encoder.c
@@ -2027,7 +2027,7 @@
   YV12_BUFFER_CONFIG *unscaled = cpi->unscaled_source;
   InterpFilter filter_scaler =
       cpi->use_svc ? svc->downsample_filter_type[svc->spatial_layer_id]
-                   : EIGHTTAP_REGULAR;
+                   : EIGHTTAP_SMOOTH;
   int phase_scaler =
       cpi->use_svc ? svc->downsample_filter_phase[svc->spatial_layer_id] : 0;