gcc 5.1.1 and warnings when building fio on Linux with -flto

[Bruce Cran <bruce@cran.org.uk>]

Noticed the following warnings when building fio on Linux with gcc 5.1.1 
and -flto:

debug.h:38:22: warning: type of ‘fio_debug’ does not match original 
declaration
  extern unsigned long fio_debug;
                       ^
t/debug.c:5:14: note: previously declared here
  unsigned int fio_debug = 0;


lib/libmtd.c: In function ‘mtd_get_dev_info1’:
lib/libmtd.c:751:46: warning: passing argument 3 of ‘dev_read_data’ 
discards ‘const’ qualifier from pointer target type 
[-Wdiscarded-array-qualifiers]
   ret = dev_read_data(lib->mtd_name, mtd_num, &mtd->name,
                                               ^
lib/libmtd.c:184:12: note: expected ‘void *’ but argument is of type 
‘const char (*)[128]’
  static int dev_read_data(const char *patt, int mtd_num, void *buf, int 
buf_len)
             ^
lib/libmtd.c:757:46: warning: passing argument 3 of ‘dev_read_data’ 
discards ‘const’ qualifier from pointer target type 
[-Wdiscarded-array-qualifiers]
   ret = dev_read_data(lib->mtd_type, mtd_num, &mtd->type_str,
                                               ^
lib/libmtd.c:184:12: note: expected ‘void *’ but argument is of type 
‘const char (*)[65]’
  static int dev_read_data(const char *patt, int mtd_num, void *buf, int 
buf_len)


-- 
Bruce