am 397a3642: fs_mgr: check that fstab is not NULL in fs_mgr_free_fstab

* commit '397a3642145dbd0919f8148ff24f0cafe1714b55':
  fs_mgr: check that fstab is not NULL in fs_mgr_free_fstab
diff --git a/fs_mgr/fs_mgr.c b/fs_mgr/fs_mgr.c
index 81ae703..13b71ee 100644
--- a/fs_mgr/fs_mgr.c
+++ b/fs_mgr/fs_mgr.c
@@ -377,6 +377,10 @@
 {
     int i;
 
+    if (!fstab) {
+        return;
+    }
+
     for (i = 0; i < fstab->num_entries; i++) {
         /* Free the pointers return by strdup(3) */
         free(fstab->recs[i].blk_device);