libxshmfence: Changes to 'master'

[Keith Packard]

 configure.ac          |   13 +++++++++++--
 src/xshmfence_futex.h |   24 ++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 2 deletions(-)

New commits:
commit 9c4f070e1304a3503cfab08f68573443025fc4c9
Author: Keith Packard <keithp at keithp.com>
Date:   Tue Jun 17 13:45:24 2014 -0700

    Use /dev/shm as an optional shared memory directory
    
    This is the path coded into glibc, so it should exist and be useful on
    any glibc-based system
    
    Signed-off-by: Keith Packard <keithp at keithp.com>

commit d3efccb33fa599d48004b22f2e07a19da4aaf789
Author: Jung-uk Kim <jkim at FreeBSD.org>
Date:   Mon Dec 9 18:35:45 2013 -0500

    Add support for FreeBSD using umtx (v3).
    
    This fixes a sign-extension bug in the previous versions.
    
    Signed-off-by: Jung-uk Kim <jkim at FreeBSD.org>
    Signed-off-by: Keith Packard <keithp at keithp.com>