zephyr: Bring in the Zephyr build
Add support for building mcuboot as a Zephyr application. This is
copied from the iotboot repo with some minor reorganization to work with
the mcuboot directory layout.
diff --git a/zephyr/include/os/os_malloc.h b/zephyr/include/os/os_malloc.h
new file mode 100644
index 0000000..32b72c2
--- /dev/null
+++ b/zephyr/include/os/os_malloc.h
@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef H_OS_MALLOC_
+#define H_OS_MALLOC_
+
+#include "os/os_heap.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#undef malloc
+#define malloc os_malloc
+
+#undef free
+#define free os_free
+
+#undef realloc
+#define realloc os_realloc
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif