lapi/seek.h: fix typo for SEEK_DATA

Compilation failed on RHEL6.9GA because SEEK_DATA is not defined.

Signed-off-by: Xiao Yang <yangx.jy@cn.fujitsu.com>
Acked-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/include/lapi/seek.h b/include/lapi/seek.h
index fe1999f..023f1fb 100644
--- a/include/lapi/seek.h
+++ b/include/lapi/seek.h
@@ -20,8 +20,8 @@
 
 #include <unistd.h>
 
-#ifndef DATA_HOLE
-# define DATA_HOLE 4
+#ifndef SEEK_DATA
+# define SEEK_DATA 3
 #endif
 
 #ifndef SEEK_HOLE