Move error_code.h into otautil.

This way it stops requiring relative path ".." in LOCAL_C_INCLUDES
(uncrypt and edify). Soong doesn't accept non-local ".." in
"local_include_dirs".

Test: mmma bootable/recovery
Change-Id: Ia4649789cef2aaeb2785483660e9ea5a8b389c62
diff --git a/tests/component/updater_test.cpp b/tests/component/updater_test.cpp
index 2a0575a..e35870d 100644
--- a/tests/component/updater_test.cpp
+++ b/tests/component/updater_test.cpp
@@ -39,8 +39,8 @@
 
 #include "common/test_constants.h"
 #include "edify/expr.h"
-#include "error_code.h"
 #include "otautil/SysUtil.h"
+#include "otautil/error_code.h"
 #include "print_sha1.h"
 #include "updater/blockimg.h"
 #include "updater/install.h"