[FIX] point_of_sale: Fix cleaning git between 2 version of iot

When iot switch between 2 version of odoo we must clean correctly the branch.

Now -dfx erases each and every file in git directory which is not part of repository.
(like drivers and interfaces)

closes odoo#95698

X-original-commit: c115f9f
Signed-off-by: Masereel Pierre <pim@odoo.com>

addons/point_of_sale/tools/posbox/configuration/posbox_update.sh

@@ -13,7 +13,7 @@ echo "addons/point_of_sale/tools/posbox/overwrite_after_init/home/pi/odoo" >> .g
 git fetch "${localremote}" "${localbranch}" --depth=1
 git reset "${localremote}"/"${localbranch}" --hard
 
-git clean -df
+git clean -dfx
 cp -a /home/pi/odoo/addons/point_of_sale/tools/posbox/overwrite_after_init/home/pi/odoo/* /home/pi/odoo/
 rm -r /home/pi/odoo/addons/point_of_sale/tools/posbox/overwrite_after_init