[bootlin/training-materials updates] master: Boot time labs: clarify instructions (8d4b2cfd)

[Michael Opdenacker]

Repository : https://github.com/bootlin/training-materials
On branch  : master
Link       : https://github.com/bootlin/training-materials/commit/8d4b2cfdff0c11f5a40ecebed12bae0c61110ce8

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commit 8d4b2cfdff0c11f5a40ecebed12bae0c61110ce8
Author: Michael Opdenacker <michael.opdenacker at bootlin.com>
Date:   Fri Apr 9 12:06:42 2021 +0200

    Boot time labs: clarify instructions
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at bootlin.com>


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

8d4b2cfdff0c11f5a40ecebed12bae0c61110ce8
 .../boot-time-filesystem-optimizations.tex                     | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/labs/boot-time-filesystem-optimizations/boot-time-filesystem-optimizations.tex b/labs/boot-time-filesystem-optimizations/boot-time-filesystem-optimizations.tex
index d7993523..307e3833 100644
--- a/labs/boot-time-filesystem-optimizations/boot-time-filesystem-optimizations.tex
+++ b/labs/boot-time-filesystem-optimizations/boot-time-filesystem-optimizations.tex
@@ -92,8 +92,14 @@ So:
     any additional option.
    \item Add the following line to the \code{/playvideo} file:\\
    \code{mount -t devtmpfs nodev /dev}
-   \item Run \code{make} to update your root filesystem and then
-   extract it again in your \code{rootfs} directory.
+   \item Run \code{make} to update your root filesystem.
+   \item Then extract it in your \code{rootfs} directory:
+\begin{verbatim}
+cd ..
+mkdir rootfs
+cd rootfs
+tar xvf ../buildroot/output/images/rootfs.tar
+\end{verbatim}
    \end{itemize}
 \item Go to the U-Boot command line on your board, and modify the
 kernel parameters:\\