av1_loop_restoration_filter_frame_init: fix alloc check

aom_realloc_frame_buffer was changed to return an error code (which are
all positive values) in:
02affebbe Return error code for buffer allocation.

Bug: aomedia:3276
Change-Id: Icb8853479cb954cda194c900468f96de2670772b
diff --git a/av1/common/restoration.c b/av1/common/restoration.c
index 709cf48..822f240 100644
--- a/av1/common/restoration.c
+++ b/av1/common/restoration.c
@@ -1117,7 +1117,7 @@
   if (aom_realloc_frame_buffer(
           lr_ctxt->dst, frame_width, frame_height, seq_params->subsampling_x,
           seq_params->subsampling_y, highbd, AOM_RESTORATION_FRAME_BORDER,
-          cm->features.byte_alignment, NULL, NULL, NULL, 0, 0) < 0)
+          cm->features.byte_alignment, NULL, NULL, NULL, 0, 0) != AOM_CODEC_OK)
     aom_internal_error(cm->error, AOM_CODEC_MEM_ERROR,
                        "Failed to allocate restoration dst buffer");