ui: misc fixes which piled up during 3.0 release freeze

# gpg: Signature made Mon 27 Aug 2018 09:53:07 BST
# gpg:                using RSA key 4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/ui-20180827-v4-pull-request:
  util: promote qemu_egl_rendernode_open() to libqemuutil
  dmabuf: add y0_top, pass it to spice
  ui/vnc: Remove useless parenthesis around DIV_ROUND_UP macro
  ui/sdl2: Fix broken -full-screen CLI option
  spice-display: fix qemu_spice_cursor_refresh_bh locking
  spice-display: access ptr_x/ptr_y under Mutex
  vnc: remove support for deprecated tls, x509, x509verify options
  doc: switch to modern syntax for VNC TLS setup
  sdl2: redraw correctly when scanout_mode enabled.
  ui: use enum to string helpers
  vnc: fix memleak of the "vnc-worker-output" name
  ui/sdl2: Remove the obsolete SDL_INIT_NOPARACHUTE flag
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>