Allow client to force server to terminate if it exits

This is intended to be used by screen lockers, where the server must
exit if the screen locker does, to avoid a security hole.  As suggested
by Alan Coopersmith, this is implemented using a new flag for the
disconnect mode of the XFixes extension.
9 jobs for DemiMarie-master-patch-34896 in 2 minutes and 28 seconds (queued for 1 second)
Status Name Job ID Coverage
  Prep
passed container-prep #12001428

00:00:21

 
  Build
passed autotools: [] #12001431

00:00:52

passed autotools: [--enable-legacy] #12001432

00:00:43

passed meson: [] #12001429

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passed meson: [-Dlegacy=true] #12001430

00:00:19

 
  Test
passed check evdev keysyms #12001435

00:00:26

passed check versions are in sync #12001436

00:01:11

passed compare meson and autotools #12001434

00:00:37

passed meson from tarball #12001433

00:00:24