Fix return value of function

Signed-off-by: Fabio Utzig <utzig@apache.org>
Signed-off-by: David Brown <david.brown@linaro.org>
diff --git a/boot/bootutil/src/loader.c b/boot/bootutil/src/loader.c
index 82d39f8..3a30bc8 100644
--- a/boot/bootutil/src/loader.c
+++ b/boot/bootutil/src/loader.c
@@ -262,7 +262,7 @@
 
 done:
     flash_area_close(fap);
-    return 0;
+    return rc;
 }
 
 static int