hconst.ph: need to numify integerizations

When calculating symbol values, we will need to convert them to Perl
scalars at the end, or usbdescgen.pl will fail horribly.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

tools/perlinc/hconst.ph

@@ -86,7 +86,7 @@ sub header_const($) {
 	    }
 	}
 
-	$syms{$s} = eval("{ use bigint; return ($o$e); }");
+	$syms{$s} = eval("{ use bigint; return Math::BigInt->new($o$e)->numify(); }");
     }
 
     return %syms;