Make qemu-plugin.h consumable for C++ platform.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/qemu/qemu-plugin.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 214b12bfd6..8637e3d8cf 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -16,6 +16,8 @@
 #include <stdbool.h>
 #include <stddef.h>
 
+G_BEGIN_DECLS
+
 /*
  * For best performance, build the plugin with -fvisibility=hidden so that
  * QEMU_PLUGIN_LOCAL is implicit. Then, just mark qemu_plugin_install with
@@ -723,4 +725,6 @@ qemu_plugin_get_register_files(unsigned int vcpu_index, int *size);
  */
 int qemu_plugin_read_register(GByteArray *buf, int reg);
 
+G_END_DECLS
+
 #endif /* QEMU_QEMU_PLUGIN_H */
-- 
2.42.0