libzbc: support C++

Declare all user functions extern "C" when included from a C++
application.

Signed-off-by: Damien Le Moal <[email protected]>

Author: damien-lemoal

include/libzbc/zbc.h

@@ -14,6 +14,10 @@
 #ifndef _LIBZBC_H_
 #define _LIBZBC_H_
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include <stdio.h>
 #include <unistd.h>
 #include <stdbool.h>
@@ -1160,4 +1164,8 @@ extern int zbc_flush(struct zbc_device *dev);
  * @}
  */
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _LIBZBC_H_ */