Fix build with 64 bits time_t

Fix build with 64 bits time_t

time element is deprecated on new input_event structure in kernel's
input.h [1]

This will avoid the following build failure:

hw/input/virtio-input-host.c: In function 'virtio_input_host_handle_status':
hw/input/virtio-input-host.c:198:28: error: 'struct input_event' has no member named 'time'
  198 |     if (gettimeofday(&evdev.time, NULL)) {
      |                            ^

Fixes:
 - http://autobuild.buildroot.org/results/a538167e288c14208d557cd45446df86d3d599d5
 - http://autobuild.buildroot.org/results/efd4474fb4b6c0ce0ab3838ce130429c51e43bbb

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=152194fe9c3f

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Message-Id: <20201203195819.583626-1-fontaine.fabrice@gmail.com>
Fixes: https://gitlab.com/qemu-project/qemu/-/issues/246
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>