mesa: use strtok_s for strtok_r on windows
mesa: use strtok_s for strtok_r on windows

https://msdn.microsoft.com/en-us/library/ftsafwz3.aspx

v2: use _WIN32 instead of _MSC_VER (Brian Paul)

Signed-off-by: Tapani Pälli <cdcb67a5e49297de94340ca09f25994bd5e7f762@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92183
Reviewed-by: Brian Paul <3cb4e1df5ec4da2c7c4af7c52cec8cf340a55a10@vmware.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler