[FE training-materials-updates] Clarify some UBI lab instructions

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=ea8be2f46a1c5e99edc3f7c091f056e5dbc27952

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commit ea8be2f46a1c5e99edc3f7c091f056e5dbc27952
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Wed Nov 4 17:01:33 2015 +0100

    Clarify some UBI lab instructions
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


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ea8be2f46a1c5e99edc3f7c091f056e5dbc27952
 labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex b/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
index cff9deb..3e616c8 100644
--- a/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
+++ b/labs/sysdev-flash-filesystems/sysdev-flash-filesystems.tex
@@ -53,8 +53,10 @@ board.
 Prepare a UBIFS filesystem image containing the files stored in the
 \code{/www/upload/files} directory.
 
-Modify the \code{/etc/init.d/rcS} file to mount the \code{data} volume
-on \code{/var/www/files}.
+Modify the \code{/etc/init.d/rcS} file to mount a UBI volume called
+\code{data} \footnote{We will create it when running \code{ubinize}
+in the next section} on \code{/var/www/files}.
+
 Once done, create a UBIFS image of your root filesystem.
 
 \section{UBI image preparation}