Fix C++ build following commit ab1478f7146843f7.

For C++, ab1478f7146843f7 inadvertently defined XS_INTERNAL as
    extern "C" static ...
which C++ compilers rightfully choke on.

diff --git a/XSUB.h b/XSUB.h
index 5a5fc63..f4623e9 100644 (file)
--- a/XSUB.h
+++ b/XSUB.h
@@ -144,7 +144,7 @@ is a lexical $_ in scope.
 #  else
 #    ifdef __cplusplus
 #      define XS_EXTERNAL(name) extern "C" XSPROTO(name)
-#      define XS_INTERNAL(name) extern "C" STATIC XSPROTO(name)
+#      define XS_INTERNAL(name) static XSPROTO(name)
 #    else
 #      define XS_EXTERNAL(name) XSPROTO(name)
 #      define XS_INTERNAL(name) STATIC XSPROTO(name)