buildroot

apply-patches.sh: don't print anything when "make -s" is used

The make "-s" option is used to enable the "Silent operation" so if that
option is used don't print anything as far as there isn't any error.

Add the "-s" option to "apply-patches.sh" to enable silent operation.

[Peter: use the existing QUIET variable]
Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>