bug#21580: runcon flask.h warning

[Andreas Grünbacher]

Hello,

on a Fedora 23 Beta system, coreutils currently doesn't build because
of the following warning which is treated as an error:

  CC       src/runcon.o
In file included from src/runcon.c:49:0:
/usr/include/selinux/flask.h:5:2: error: #warning "Please remove any
#include's of this header in your source code." [-Werror=cpp]
 #warning "Please remove any #include's of this header in your source code."
  ^
/usr/include/selinux/flask.h:6:2: error: #warning "Instead, use
string_to_security_class() to map the class name to a value."
[-Werror=cpp]
 #warning "Instead, use string_to_security_class() to map the class
name to a value."
  ^
cc1: all warnings being treated as errors
Makefile:8811: recipe for target 'src/runcon.o' failed

Andreas