Merge remote-tracking branch 'remotes/kraxel/tags/pull-input-5' into staging

input: fixes for the rewrite.

# gpg: Signature made Mon 10 Mar 2014 12:50:25 GMT using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <[email protected]>"
# gpg:                 aka "Gerd Hoffmann <[email protected]>"
# gpg:                 aka "Gerd Hoffmann (private) <[email protected]>"

* remotes/kraxel/tags/pull-input-5:
  input: map INPUT_BUTTON_WHEEL_{UP,DOWN} to legacy input z axis moves.
  input: sdl: fix guest_cursor logic.

Signed-off-by: Peter Maydell <[email protected]>