c++: improve typing

[Akim Demaille]

commit 6a61b6b17ead27f659083cf5ce2faa5f63911ff6
Author: Akim Demaille <akim.demai...@gmail.com>
Date:   Sat Nov 30 16:57:55 2019 +0100

    c++: improve typing
    
    * data/skeletons/lalr1.cc (yysyntax_error_): symbol_type::type_get
    returns a symbol_number_type (which is indeed an int).

diff --git a/data/skeletons/lalr1.cc b/data/skeletons/lalr1.cc
index 64ff81a3..121b524d 100644
--- a/data/skeletons/lalr1.cc
+++ b/data/skeletons/lalr1.cc
@@ -1330,7 +1330,7 @@ b4_error_verbose_if([state_type yystate, const 
symbol_type& yyla],
     */
     if (!yyla.empty ())
       {
-        int yytoken = yyla.type_get ();
+        symbol_number_type yytoken = yyla.type_get ();
         yyarg[yycount++] = yytname_[yytoken];]b4_lac_if([[
 
 #if ]b4_api_PREFIX[DEBUG