overlay: writeback: Add dumpsys info

Add dumpsys information from writeback data structure.
Remove some unused fields, formatting to save space.

Change-Id: I808ce67aae16e27c3aa6d6db45983929b1386b69
diff --git a/liboverlay/overlayUtils.cpp b/liboverlay/overlayUtils.cpp
index fd8bfe2..1377182 100644
--- a/liboverlay/overlayUtils.cpp
+++ b/liboverlay/overlayUtils.cpp
@@ -427,9 +427,8 @@
         const msmfb_data& ov) {
     char str_data[256] = {'\0'};
     snprintf(str_data, 256,
-            "%s offset=%d memid=%d id=%d flags=0x%x priv=%d\n",
-            prefix, ov.offset, ov.memory_id, ov.id, ov.flags,
-            ov.priv);
+            "%s offset=%d memid=%d id=%d flags=0x%x\n",
+            prefix, ov.offset, ov.memory_id, ov.id, ov.flags);
     strncat(buf, str_data, strlen(str_data));
 }