libxl: disable usbredirection if spice is disabled

Now if usbredirection is enabled in domU's xl cfg is added also
if spice is disabled and then usbredirection remain unused.
This patch is usbredirection is enabled but spice not disable
usbredirection and show a warning.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
tools: various things just for fast test build

- Remove python prefix
- Add/remove/stop of main services (xencommons, xendomains)

NOTE:
This patch is only for do fast test build with make debball
and upstream qemu build with spice full features.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>

---

Changes from v2:
- remove add of spice and usbredir on upstream qemu build

Changes from v1:
- Added: Add/remove/stop of main services
libxl: Add qxl vga interface support for upstream qemu

Usage:
  vga="qxl"

Qxl vga support many resolutions that not supported by stdvga,
mainly the 16:9 ones and other high up to 2560x1600.
With QXL you can get improved performance and smooth video also
with high resolutions and high quality.
Require their drivers installed in the domU and spice used
otherwise act as a simple stdvga.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
Signed-off-by: Zhou Peng <zpengxen@gmail.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>

---

Changes in v16:
- refresh
- improved commit description

Changes in v15:
- refresh
- small code improvements in libxl_dm.c

Changes in v14:
- refresh
- update qemu parameters (from -vga to -device)

NOTES:
Works correctly with windows domUs, tested on windows 7 64 bit
with qxl driver from spice guest tools 0.74.
I tested some resolution not supported by stdvga (1366x768, 1600x900
and 1920x1080) with 32 bit color and all works good equal to kvm.
For now not works on linux domUs when xorg have 100% cpu and black
screen with qxl driver installed.
Seems needed other changes/fixes on xen and/or xorg/qxl driver side
before have it full working with linux domUs.
Hvmloader: Modify ACPI to only supply _EJ0 methods for PCIslots that support hotplug by runtime patching

In Xen platform, after using upstream qemu, the all of pci devices will show
hotplug in the windows guest. In this situation, the windows guest may occur
blue screen when VM' user click the icon of VGA card for trying unplug VGA card.
However, we don't hope VM's user can do such dangerous operation, and showing
all pci devices inside the guest OS is unfriendly.

This is done by runtime patching:
  - Rename _EJ0 methods for PCI slots in DSDT to EJ0_:note that this has the
    same checksum, but is ignored by OSPM.
  - At compile time, look for these methods in ASL source,find the matching AML,
    and store the offsets of these methods in a table named aml_ej0_data.
  - At run time, go over aml_ej0_data, check which slots not support hotplug and
    patch the ACPI table, replacing _EJ0 with EJ0_.

Signed-off-by: Gaowei <gao.gaowei@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
libxl: add basic spice support for pv domUs

This patch adds basic spice support for pv domUs.
The qemu parameters are the same as the hvm ones and they works.
Therefore xl cfg parameters are the same as the hvm ones except that
features not supported yet by pv domUs (vdagent and usbredirection)
are kept disabled by default.
It also enables vfb and vkb required to have basic spice working.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>

---

Notes:
- The vfb part is only a draft and needs to be improved.
- Patch is tested and working, except for the pointer not
  visible in some cases with pv domUs but always working.
- I not use the api, test the u.hvm.spice retro-compatibility with
  api is needed.

Any feedback is appreciated.

Changes in v6:
- refresh libxl_create.c

Changes in v5:
- libxl_create.c: * don't copy u.hvm.spice in the newer if
  the newer is already used
  * set default for all spice bool options in any case
  * spice features not supported in pv will be disabled and
  will show a warning about them if was setted enabled
- xl_cmdimpl.c: parse all spice options out of hvm part
- libxl_dm.c: changed some forgotten u.hvm.spice to spice

Changes in v4:
- added libxl.h changes
- libxl_create.c: added older u.hvm.spice compatibility
  copying it in newer one

Changes in v3:
- xl.cfg.pod.5: moved spice out of hvm section and specified
  the features for now hvm only.
- libxl_types.idl: added spice struct out of keyedunion hvm only.
- use new generic spice struct instead of hvm only ones.

Changes in v2:
- xl_cmdimpl.c: always set vnc and sdl toplevel parameters in &vfb
  with vnc or spice enabled on pv domUs otherwise in some cases it
  would fail with error for one bool default value missing.
- libxl_dm.c: do not add -nographic if spice is enabled, even though
  -nographic seems buggy in upstream qemu.
libxl: Spice image compression setting support for upstream qemu

Usage:
spice_image_compression=[auto_glz|auto_lz|quic|glz|lz|off]

Specifies what image compression is to be used by spice (if given),
otherwise the qemu default will be used.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>
libxl: Spice streaming video setting support for upstream qemu

Usage:
spice_streaming_video=[filter|all|off]

Specifies what streaming video setting is to be used by spice (if given),
otherwise the qemu default will be used.

Signed-off-by: Fabio Fantoni <fabio.fantoni@m2r.biz>