gindent: Fix type incompatibility introduced with gperf 3.1
The patch is based on the idea proposed by gnw3. I tried this on a clean
build with macports 2.4.1 on El Capitan 10.11.6
The problem was introduced with gperf 3.1 resulting in a build
see: https://trac.macports.org/ticket/54466
===============================================================================
--- src/lexi.c.orig 2017-08-27 18:33:16.000000000 +0200
+++ src/lexi.c 2017-08-27 18:35:22.000000000 +0200
-templ_ty *is_reserved (const char *str, unsigned int len);
+templ_ty *is_reserved (const char *str, size_t len);
-templ_ty *is_reserved_cc (register const char *str, register unsigned int len);
+templ_ty *is_reserved_cc (register const char *str, register size_t len);