qemu: Add support for emulatorsched

This helps in a scenarios where vCPUs run with a priority that is so high they
might starve the emulator thread.  And it also fits with the rest of the
settings.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

src/qemu/qemu_process.c

@@ -2683,7 +2683,7 @@ qemuProcessSetupEmulator(virDomainObjPtr vm)
                                0, vm->def->cputune.emulatorpin,
                                vm->def->cputune.emulator_period,
                                vm->def->cputune.emulator_quota,
-                               NULL);
+                               vm->def->cputune.emulatorsched);
 }