fs_mgr_priv: Extend fs wait timeout to 20 seconds

In practice 5 seconds is too short to wait for a disk device node to
show up if the disk is USB; 20 seconds is a much more comfortable
window.

Change-Id: Iaf2c1f46b41a44fc1240d52d8498ca9cb639ea80
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
diff --git a/fs_mgr/fs_mgr_priv.h b/fs_mgr/fs_mgr_priv.h
index 175fdab..7d54ca6 100644
--- a/fs_mgr/fs_mgr_priv.h
+++ b/fs_mgr/fs_mgr_priv.h
@@ -35,7 +35,7 @@
     char *key_loc;
 };
 
-#define WAIT_TIMEOUT 5
+#define WAIT_TIMEOUT 20
 
 /* fstab has the following format:
  *