Suggested by Petter <petter@mykolab.ch>
and Mark H Weaver <mhw@netris.org>.
Reported by Duncan Keall <duncan@duncankeall.com>.
Partly fixes <http://bugs.gnu.org/19190> by populating /dev/mapper
early enough.
* gnu/build/linux-boot.scm (mount-essential-file-systems): Mount /dev as
a devtmpfs.
(move-essential-file-systems): Add /dev.
(mount-root-file-system): Mount /rw-root/dev as a devtmpfs instead of
calling 'make-essential-device-nodes'.
(boot-system): Remove call to 'make-essential-device-nodes'.
* gnu/system/file-systems.scm (%devtmpfs-file-system): Remove.
* doc/guix.texi (File Systems): Adjust accordingly.
cc0e575a94