Automatically detect /datadata from recovery.fstab. Remove BOARD_HAS_DATADATA.

Change-Id: I28d3c7a6beaacd77c67c5af0ae3464acfd2572e3
diff --git a/extendedcommands.h b/extendedcommands.h
index 650a519..e9d7cc4 100644
--- a/extendedcommands.h
+++ b/extendedcommands.h
@@ -44,3 +44,5 @@
 wipe_battery_stats();
 
 void create_fstab();
+
+int has_datadata();
\ No newline at end of file