Use aom_writer with generic_encode().

Change the generic_encode() function to take an aom_writer struct
 instead of an od_ec_enc struct.

Change-Id: Icb447fe5ada27aba45fbaea08b28e9fe42c5a404
diff --git a/av1/encoder/encodemb.c b/av1/encoder/encodemb.c
index a76443a..6573af9 100644
--- a/av1/encoder/encodemb.c
+++ b/av1/encoder/encodemb.c
@@ -1186,13 +1186,9 @@
 
   // Encode residue of DC coeff, if required.
   if (!has_dc_skip || out_int32[0]) {
-#if CONFIG_DAALA_EC
-    generic_encode(&daala_enc->w.ec, &daala_enc->state.adapt.model_dc[plane],
+    generic_encode(&daala_enc->w, &daala_enc->state.adapt.model_dc[plane],
                    abs(out_int32[0]) - has_dc_skip, -1,
                    &daala_enc->state.adapt.ex_dc[plane][tx_size][0], 2);
-#else
-#error "CONFIG_PVQ currently requires CONFIG_DAALA_EC."
-#endif
   }
   if (out_int32[0]) {
     aom_write_bit(&daala_enc->w, out_int32[0] < 0);