Simplify conditional expressions

Convert

  if (A) {
    foo;
  } else {
    if (B || C)
      foo;
  }

to the equivalent

  if (A || B || C) {
    foo;
  }

Bug: aomedia:3534
Change-Id: Ie2fd39a07b9d7e6b1193b2baeac338ee86c10180
(cherry picked from commit 8c56649d7962c47ddc554684e060e33214bb668c)
diff --git a/av1/encoder/encoder.c b/av1/encoder/encoder.c
index 878f69f..07b6ffe 100644
--- a/av1/encoder/encoder.c
+++ b/av1/encoder/encoder.c
@@ -2588,21 +2588,17 @@
     if (cpi->ref_frame_flags & av1_ref_frame_flag_list[GOLDEN_FRAME]) {
       const YV12_BUFFER_CONFIG *const ref =
           get_ref_frame_yv12_buf(cm, GOLDEN_FRAME);
-      if (ref == NULL) {
+      if (ref == NULL || ref->y_crop_width != cm->width ||
+          ref->y_crop_height != cm->height) {
         cpi->ref_frame_flags ^= AOM_GOLD_FLAG;
-      } else {
-        if (ref->y_crop_width != cm->width || ref->y_crop_height != cm->height)
-          cpi->ref_frame_flags ^= AOM_GOLD_FLAG;
       }
     }
     if (cpi->ref_frame_flags & av1_ref_frame_flag_list[ALTREF_FRAME]) {
       const YV12_BUFFER_CONFIG *const ref =
           get_ref_frame_yv12_buf(cm, ALTREF_FRAME);
-      if (ref == NULL) {
+      if (ref == NULL || ref->y_crop_width != cm->width ||
+          ref->y_crop_height != cm->height) {
         cpi->ref_frame_flags ^= AOM_ALT_FLAG;
-      } else {
-        if (ref->y_crop_width != cm->width || ref->y_crop_height != cm->height)
-          cpi->ref_frame_flags ^= AOM_ALT_FLAG;
       }
     }
   }