resize: Clear above context to aligned width

This fixes an issue with context clearing introduced by commit
5e81643d31a44e55308bd71570d1f9732e462bbb.

In av1_zero_above_context width_y went from being assigned "2 *
aligned_width" to "width << 1". All this patch does is replace width
with the aligned_width.

This resolves an issue with random resizing being broken on the master
branch.

Change-Id: Ib60bf81e6091802053a5a26057c626d4efe6497c
diff --git a/av1/common/onyxc_int.h b/av1/common/onyxc_int.h
index 3dc2a48..186ef16 100644
--- a/av1/common/onyxc_int.h
+++ b/av1/common/onyxc_int.h
@@ -866,7 +866,7 @@
   const int aligned_width = ALIGN_POWER_OF_TWO(width, cm->mib_size_log2);
 
   const int offset_y = mi_col_start << (MI_SIZE_LOG2 - tx_size_wide_log2[0]);
-  const int width_y = width << (MI_SIZE_LOG2 - tx_size_wide_log2[0]);
+  const int width_y = aligned_width << (MI_SIZE_LOG2 - tx_size_wide_log2[0]);
   const int offset_uv = offset_y >> cm->subsampling_x;
   const int width_uv = width_y >> cm->subsampling_x;