Drop unneeded pthread.h inclusions

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

hw/xen_nic.c

@@ -25,7 +25,6 @@
 #include <inttypes.h>
 #include <fcntl.h>
 #include <errno.h>
-#include <pthread.h>
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>

hw/xics.c

@@ -29,8 +29,6 @@
 #include "hw/spapr.h"
 #include "hw/xics.h"
 
-#include <pthread.h>
-
 /*
  * ICP: Presentation layer
  */

ui/spice-display.c

@@ -15,8 +15,6 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <pthread.h>
-
 #include "qemu-common.h"
 #include "qemu-spice.h"
 #include "qemu-timer.h"