Annotate repr(C) for enums

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>

Author: elmarco

src/color/imp.rs

@@ -2,6 +2,7 @@ use glib::translate::IntoGlib;
 
 #[derive(Debug, Copy, Clone, glib::GEnum)]
 #[genum(type_name = "ExColor")]
+#[repr(C)]
 pub enum Color {
     Red,
     Green,

src/flags/imp.rs

@@ -1,4 +1,7 @@
-#[glib::gflags("ExFlags")]
+use glib::gflags;
+
+#[gflags("ExFlags")]
+#[repr(C)]
 pub enum Flags {
     SOME = 0b00000001,
     ZING = 0b00000010,