gnu: Add perl-x11-xcb.

* gnu/packages/xorg.scm (perl-x11-xcb): New variable.

gnu: sessreg: Update to 1.1.1.

* gnu/packages/xorg.scm (sessreg): Update to 1.1.1.

Merge branch 'master' into python-tests

gnu: Remove xf86-video-modesetting.

This is part of xorg-server since version 1.17:

https://cgit.freedesktop.org/xorg/xserver/commit/?id=35dc7c75150733dbcef8a18b6796f49a7c48ebee

* gnu/packages/xorg.scm (xf86-video-modesetting): Remove variable.
* gnu/services/xorg.scm (xorg-configuration-file, %default-xorg-modules):
Adjust accordingly.

Merge branch 'master' into python-tests

gnu: xf86-video-intel: Update to 2.99.917-3-e4fe79c.

* gnu/packages/xorg.scm (xf86-video-intel): Update to 2.99.917-3-e4fe79c.

gnu: xf86-input-libinput: Update to 0.24.0.

* gnu/packages/xorg.scm (xf86-input-libinput): Update to 0.24.0.

gnu: xf86-video-intel: Update to 2.99.917-2-9fe04af.

* gnu/packages/xorg.scm (xf86-video-intel): Update to 2.99.917-2-9fe04af.

gnu: xcalc: Update to 1.0.6.

* gnu/packages/xorg.scm (xcalc): Update to 1.0.6.

gnu: xauth: Update to 1.0.10.

* gnu/packages/xorg.scm (xauth): Update to 1.0.10.

gnu: Add xcalc.

* gnu/packages/xorg.scm (xcalc): New variable.

gnu: xf86-input-evdev: Update to 2.10.5.

* gnu/packages/xorg.scm (xf86-input-evdev): Update to 2.10.5.

gnu: xf86-video-r128: Update to 6.10.2.

* gnu/packages/xorg.scm (xf86-video-r128): Update to 6.10.2.

gnu: xf86-video-savage: Update to 2.3.9.

* gnu/packages/xorg.scm (xf86-video-savage): Update to 2.3.9.

gnu: xf86-video-trident: Update to 1.3.8.

* gnu/packages/xorg.scm (xf86-video-trident): Update to 1.3.8.

gnu: xf86-video-glint: Update to 1.2.9.

* gnu/packages/xorg.scm (xf86-video-glint): Update to 1.2.9.
[source]: Remove upstreamed patch.
* gnu/packages/patches/xf86-video-glint-remove-mibstore.patch: Delete file.
* gnu/local.mk (dist_patch_DATA): Remove it.

gnu: xf86-video-nv: Update to 2.1.21.

* gnu/packages/xorg.scm (xf86-video-nv): Update to 2.1.21.
[source]: Remove upstreamed patch.
* gnu/packages/patches/xf86-video-nv-remove-mibstore.patch: Delete file.
* gnu/local.mk (dist_patch_DATA): Remove it.

gnu: xf86-video-siliconmotion: Update to 1.7.9.

* gnu/packages/xorg.scm (xf86-video-siliconmotion): Update to 1.7.9.

gnu: xf86-video-mga: Update to 1.6.5.

* gnu/packages/xorg.scm (xf86-video-mga): Update to 1.6.5.

gnu: xf86-video-sis: Update to 0.10.9.

* gnu/packages/xorg.scm (xf86-video-sis): Update to 0.10.9.