Remove opaque pointer VP8_PTR

Use an opaque struct rather than typecasting through VP8_PTR, an int*.

Change-Id: I5ed4d9238ba2e8d51bfa07a8da87a2eb4c8fa43a
diff --git a/vp8/vp8_cx_iface.c b/vp8/vp8_cx_iface.c
index a467daa..6181ee8 100644
--- a/vp8/vp8_cx_iface.c
+++ b/vp8/vp8_cx_iface.c
@@ -83,7 +83,7 @@
     vpx_codec_enc_cfg_t     cfg;
     struct vp8_extracfg     vp8_cfg;
     VP8_CONFIG              oxcf;
-    VP8_PTR             cpi;
+    struct VP8_COMP        *cpi;
     unsigned char          *cx_data;
     unsigned int            cx_data_sz;
     vpx_image_t             preview_img;
@@ -556,7 +556,7 @@
     vpx_codec_enc_cfg_t       *cfg;
     unsigned int               i;
 
-    VP8_PTR optr;
+    struct VP8_COMP *optr;
 
     if (!ctx->priv)
     {