ps2: fix scancodes sent for Ctrl+Pause key combination

ps2: fix scancodes sent for Ctrl+Pause key combination

The 'Pause' key is special in the AT set 1 / set 2 scancode definitions.

An unmodified 'Pause' key is supposed to send

 AT Set 1:  e1 1d 45 91 9d c5 (Down)  <nothing> (Up)
 AT Set 2:  e1 14 77 e1 f0 14 f0 77 (Down)  <nothing> (Up)

which QEMU gets right. When combined with Ctrl (both left and right variants),
a different sequence is expected

 AT Set 1:  e0 46 e0 c6 (Down)  <nothing> (Up)
 AT Set 2:  e0 7e e0 f0 73 (Down)  <nothing> (Up)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-id: 20171019142848.572-8-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>