yocto: layer: Describe what the priority is for

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>

slides/yocto-layer/yocto-layer.tex

@@ -139,6 +139,8 @@ \subsection{Creating a layer}
     \item However, the \code{bitbake-layers create-layer} command helps us create new
       layers and ensures this is done right.
     \item \code{bitbake-layers create-layer -p <PRIORITY> <layer>}
+    \item The \textbf{priority} is used to elect which recipe to use when multiple layers contains the same recipe
+    \item The recipe priority takes precedence over the version number ordering
   \end{itemize}
 \end{frame}