lib: add libxpc to implement functionality needed by xpc interfaces

lib/libxpc/include/xpc/status.h

@@ -0,0 +1,12 @@
+#ifndef XPC_STATUS_H_
+#define XPC_STATUS_H_
+
+typedef enum xpc_status {
+	XPC_SUCCESS = 0,
+	XPC_ERR_BAD_STATE,
+	XPC_ERR_INVALID_ARGUMENT,
+	XPC_ERR_NO_MEMORY,
+	XPC_ERR_MEMORY_FAULT,
+} xpc_status_t;
+
+#endif