[FE training-materials-updates] Fix git clean command options

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git
On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=4a907bcc443a80f88569533e5342b5c3293f5375

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commit 4a907bcc443a80f88569533e5342b5c3293f5375
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Wed Dec 14 17:56:38 2016 +0100

    Fix git clean command options
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


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4a907bcc443a80f88569533e5342b5c3293f5375
 .../sysdev-linux-intro-compilation/sysdev-linux-intro-compilation.tex   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/slides/sysdev-linux-intro-compilation/sysdev-linux-intro-compilation.tex b/slides/sysdev-linux-intro-compilation/sysdev-linux-intro-compilation.tex
index 0082d88..1d2bf56 100644
--- a/slides/sysdev-linux-intro-compilation/sysdev-linux-intro-compilation.tex
+++ b/slides/sysdev-linux-intro-compilation/sysdev-linux-intro-compilation.tex
@@ -95,7 +95,7 @@
       \code{make distclean}
     \item If you are in a git tree, remove all files not tracked (and
       ignored) by git:\\
-      \code{git clean -fx}
+      \code{git clean -fdx}
     \end{itemize}
     \column{0.2\textwidth}
     \includegraphics[width=0.9\textwidth]{slides/sysdev-linux-intro-compilation/kernel-mrproper.png}