configure: Remove unused CONFIG_SIGEV_THREAD_ID switch

The CONFIG_SIGEV_THREAD_ID switch is unused since the related code
has been removed by commit 6d327171
("aio / timers: Remove alarm timers"), so it can safely be removed
nowadays.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1465571084-19885-1-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

configure

@@ -4181,24 +4181,6 @@ if compile_prog "" "" ; then
     posix_madvise=yes
 fi
 
-##########################################
-# check if we have usable SIGEV_THREAD_ID
-
-sigev_thread_id=no
-cat > $TMPC << EOF
-#include <signal.h>
-int main(void) {
-  struct sigevent ev;
-  ev.sigev_notify = SIGEV_THREAD_ID;
-  ev._sigev_un._tid = 0;
-  asm volatile("" : : "g"(&ev));
-  return 0;
-}
-EOF
-if compile_prog "" "" ; then
-    sigev_thread_id=yes
-fi
-
 ##########################################
 # check if trace backend exists
 
@@ -4856,7 +4838,6 @@ echo "preadv support    $preadv"
 echo "fdatasync         $fdatasync"
 echo "madvise           $madvise"
 echo "posix_madvise     $posix_madvise"
-echo "sigev_thread_id   $sigev_thread_id"
 echo "uuid support      $uuid"
 echo "libcap-ng support $cap_ng"
 echo "vhost-net support $vhost_net"
@@ -5271,9 +5252,6 @@ fi
 if test "$posix_madvise" = "yes" ; then
   echo "CONFIG_POSIX_MADVISE=y" >> $config_host_mak
 fi
-if test "$sigev_thread_id" = "yes" ; then
-  echo "CONFIG_SIGEV_THREAD_ID=y" >> $config_host_mak
-fi
 
 if test "$spice" = "yes" ; then
   echo "CONFIG_SPICE=y" >> $config_host_mak