[FE training-materials-updates] Revert "Flash labs: remove U-boot env backup partition"

[Gregory Clement]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=4c86da8e557601ec459cfd0fbf7699210142cbd1

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commit 4c86da8e557601ec459cfd0fbf7699210142cbd1
Author: Gregory CLEMENT <gregory.clement at free-electrons.com>
Date:   Tue Nov 17 08:49:47 2015 +0100

    Revert "Flash labs: remove U-boot env backup partition"
    
    This reverts commit 7a98505d9867cc91996edfa1875ce9858b7912a0.
    
    We still need to make room for the backup environment. During saveenv,
    the backup partition is updated too (first erase and then write with the
    new values) so we must not use this partition so store anything.


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4c86da8e557601ec459cfd0fbf7699210142cbd1
 labs/sysdev-flash-filesystems/flash-map.dia        | 372 ++++++++++++++++-----
 .../sysdev-flash-filesystems.tex                   |   4 +-
 labs/sysdev-kernel-cross-compiling/flash-map.dia   | 177 ++++++++--
 .../sysdev-kernel-cross-compiling.tex              |  12 +-
 labs/sysdev-u-boot/flash-map.dia                   | 149 ++++++++-
 5 files changed, 588 insertions(+), 126 deletions(-)

Diff suppressed because of size. To see it, use:

    git diff-tree --root --patch-with-stat --no-color --find-copies-harder --ignore-space-at-eol --cc 4c86da8e557601ec459cfd0fbf7699210142cbd1