turn recovery into a C++ binary

Change-Id: I423a23581048d451d53eef46e5f5eac485b77555
diff --git a/mtdutils/mtdutils.h b/mtdutils/mtdutils.h
index 45d3ebc..2708c43 100644
--- a/mtdutils/mtdutils.h
+++ b/mtdutils/mtdutils.h
@@ -19,6 +19,10 @@
 
 #include <sys/types.h>  // for size_t, etc.
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef struct MtdPartition MtdPartition;
 
 int mtd_scan_partitions(void);
@@ -53,4 +57,8 @@
 off_t mtd_find_write_start(MtdWriteContext *ctx, off_t pos);
 int mtd_write_close(MtdWriteContext *);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif  // MTDUTILS_H_