[FE training-materials-updates] Use git checkout to revert changes

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=4d29a651fa17e2c2d7f751349e2d6ba77545902a

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commit 4d29a651fa17e2c2d7f751349e2d6ba77545902a
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Tue Jan 8 15:33:21 2013 +0100

    Use git checkout to revert changes
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


>---------------------------------------------------------------

4d29a651fa17e2c2d7f751349e2d6ba77545902a
 labs/android-new-board/android-new-board.tex       |    5 +----
 .../android-system-customization.tex               |   12 ++++++++----
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/labs/android-new-board/android-new-board.tex b/labs/android-new-board/android-new-board.tex
index f9b5b1a..792bf3e 100644
--- a/labs/android-new-board/android-new-board.tex
+++ b/labs/android-new-board/android-new-board.tex
@@ -193,10 +193,7 @@ all the hardware related configuration is set in the file
 \code{BoardConfig.mk}. In the BeagleBoard product definition, find
 where the U-boot config file to use is set.
 
-Before making any change to this file, make a copy of the original file,
-for example \code{BoardConfig.mk.orig}.
-
-Now, modify the \code{BoardConfig.mk} file to use the default U-boot
+Modify the \code{BoardConfig.mk} file to use the default U-boot
 configuration for the DevKit8000 board (\code{devkit8000_config}).
 
 To avoid rebuild errors, you should remove the directory where U-boot
diff --git a/labs/android-system-customization/android-system-customization.tex b/labs/android-system-customization/android-system-customization.tex
index 0eab2d6..8a344e1 100644
--- a/labs/android-system-customization/android-system-customization.tex
+++ b/labs/android-system-customization/android-system-customization.tex
@@ -10,10 +10,14 @@ After this lab, you will be able to:
 
 \section{Setup a new product}
 
-Revert the changes you made to the beagleboard product and define a new product
-named \textit{training} instead. This product will have all the attributes of
-the beagleboard product for now, plus the extra packages we will add along the
-labs.
+Using the \code{git checkout} command on the files you modified,
+revert the changes you made to the beagleboard product and define
+a new product named \textit{training} instead\footnote{Remember
+that all the source files we have were obtained from various git
+repositories. This allows to cancel changes or to get back to
+earlier versions.}.  This product will have all the
+attributes of the beagleboard product for now, plus the extra packages
+we will add along the labs.
 
 As we are still using the same platform, the product name returned by the
 kernel doesn't change, even though we compiled a different product. Change