An included file should start at line 1.

The preprocessor was incorrectly setting the line when starting
an include file to the line it was called from instead of 1.
This would give incorrect line numbers for errors/warnings in
the included file.

ivlpp/lexor.lex

@@ -1472,7 +1472,7 @@ static void do_include()
         fprintf(depend_file, "%s\n", standby->path);
 
     if (line_direct_flag)
-        fprintf(yyout, "\n`line %u \"%s\" 1\n", istack->lineno+1, standby->path);
+        fprintf(yyout, "\n`line 1 \"%s\" 1\n", standby->path);
 
     standby->next = istack;
     standby->stringify_flag = 0;