Revert "packages: 'package-grafts' trims native inputs."

This reverts commit 91c9b5d016ac8bed127557d378c70fbc56cec0e5
following the concerns raised by Mark, Ben, and Tobias:
<https://lists.gnu.org/archive/html/guix-devel/2017-12/msg00081.html>.

Update NEWS.

services: console-font: Use 'tcsetattr' instead of invoking 'unicode_start'.

This is more robust, faster, and incidentally gets rid of remaining
"error in the finalization thread: Bad file descriptor" messages.

* gnu/services/base.scm (unicode-start): Rewrite to use 'tcgetattr' and
'tcsetattr'.
(console-font-shepherd-services)[start]: Add 'loop' to check whether
DEVICE is ready.  Tolerate EX_OSERR return from 'setfont'.
[modules]: New field.

syscalls: Define 'input-flags' for 'tcgetattr' and friends.

* guix/build/syscalls.scm (input-flags): New macro.

gnu: guix: Update snapshot to 91c9b5d.

* gnu/packages/package-management.scm (guix): Update to 91c9b5d.

gnu: ghostscript-with-cups: Turn into a public variable.

Tris allows Hydra/Cuirass to pick it up and to build its replacement.
Failing that, users have to build "ghostscript-with-cups-9.22" from
source.

* gnu/packages/cups.scm (ghostscript/cups): Move to 'ghostscript.scm'.
(cups-filters)[inputs]: Remove 'force'.
* gnu/packages/ghostscript.scm (ghostscript/cups): New variable.

packages: 'package-grafts' trims native inputs.

'package-grafts' returns a list of potentially applicable grafts, which
'cumulative-grafts' then narrows by looking at store item references and
determining the subset of the grafts that's actually applicable.

Until now, 'package-grafts' would traverse native inputs and would thus
return a large superset of the applicable grafts, since native inputs
are not in the reference graph by definition.  This patch fixes that by
having 'package-grafts' ignore entirely native inputs from the
dependency graph.

* guix/packages.scm (fold-bag-dependencies)[bag-direct-inputs*]: Add
special case for libc.
* guix/packages.scm (bag-grafts)[native-grafts, target-grafts]: Remove.
[grafts]: New procedure.
Use it.
* tests/packages.scm ("package-grafts, grafts of native inputs
ignored"): New test.

Update NEWS.

packages: 'fold-bag-dependencies' honors nativeness in recursive calls.

Previously recursive calls to 'loop' would always consider all the bag
inputs rather than those corresponding to NATIVE?.

* guix/packages.scm (fold-bag-dependencies)[bag-direct-inputs*]: New
procedure.  Use it both in the 'match' expression and in its body.

gnu: commencement: Do not graft early bootstrap packages.

By definition, these packages are not depended on at run time by any of
the packages we use.  Thus it does not make sense to inherit grafts.
Furthermore, those grafts would often lead to extra overhead for users
who would end up downloading those "-boot0" packages just to build
package replacements that are in fact not going to be used.

This reverts parts of f1597427f220b0799b9c8847768d2f5a93fe3730 and
ce27857f710ff32c05f4ba19a04a695c1cc2ce20.

Reported by Christopher Baines at
<https://lists.gnu.org/archive/html/guix-devel/2017-12/msg00058.html>.

* gnu/packages/commencement.scm (file-boot0, binutils-boot0): Use plain
'inherit' instead of 'package/inherit'.

install: Don't start sshd by default.

Reported by Christopher Baines <mail@cbaines.net>
at <https://lists.gnu.org/archive/html/guix-devel/2017-12/msg00058.html>.

* gnu/services/ssh.scm (<openssh-configuration>)[%auto-start?]: New
field.
(openssh-shepherd-service): Honor it.
* gnu/system/install.scm (%installation-services): Set '%auto-start?' to
 #f for openssh-service-type.

doc: Mention berlin.guixsd.org.

* doc/guix.texi (Substitute Server Authorization): Add note about
berlin.guixsd.org.  Nitpick.

maint: Add 'berlin.guixsd.org.pub'.

* bayfront.guixsd.org.pub: Rename to...
* berlin.guixsd.org.pub: ... this.
* Makefile.am (dist_pkgdata_DATA): Adjust accordingly.
* gnu/services/base.scm (%default-authorized-guix-keys): Likewise.

Update NEWS.

gnu: git: Remove unreliable git-svn tests.

Reported in <https://bugs.gnu.org/29546>
by Mark H Weaver <mhw@netris.org>.

* gnu/packages/version-control.scm (git)[arguments]: In 'patch-tests'
phase, delete three git-svn tests.

maint: Let 'guix system vm-image' determine the right size.

* Makefile.am (GUIXSD_VM_IMAGE_BASE): Remove.
(release): Remoev --image-size argument to 'guix system vm-image'.

maint: Add 'aarch64-linux' to the supported systems.

* Makefile.am (SUPPORTED_SYSTEMS): Add aarch64-linux.

maint: Add the '.iso' extension to installation images.

* Makefile.am (release): Add the '.iso' suffix to image files.
* doc/guix.texi (USB Stick and DVD Installation): Adjust accordingly.

doc: Merge "USB Stick Installation" and "DVD Installation".

* doc/guix.texi (USB Stick Installation): Rename to...
(USB Stick and DVD Installation): ... this.  Merge contents with...
(DVD Installation): ... this node.  Remove.

tests: Look for multi-digit column numbers in unbound variable test.

* tests/guix-system.sh: Match one or more digits in unbound-variable test.