Fix missing return in failure case.

Bug: 19517541
(cherry picked from commit 44387e81c0e2a029f6bfe54cbdbd345b1a22cf93)

Change-Id: Ib754c1cbf03387de87a00fb122fb01666b6e0407
diff --git a/src/elfxx.h b/src/elfxx.h
index 0166d79..e0343b4 100644
--- a/src/elfxx.h
+++ b/src/elfxx.h
@@ -136,6 +136,7 @@
   ei->valid = elf_w (valid_object_mapped) (ei);
   if (!ei->valid) {
     munmap (ei->u.mapped.image, ei->u.mapped.size);
+    return false;
   }
 
   ei->mapped = true;