support/download: further silence the git helper

We expresely call printf in the git helper, calls which were not
addresed in the previous silent-build patchset.

Just redirect stdout to oblivion when being silent.

Reported-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Tested-by: Fabio Porcedda <fabio.porcedda@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

support/download/git

@@ -14,7 +14,7 @@ set -e
 verbose=-v
 while getopts :q OPT; do
     case "${OPT}" in
-    q)  verbose=-q;;
+    q)  verbose=-q; exec >/dev/null;;
     \?) printf "unknown option '%s'\n" "${OPTARG}" >&2; exit 1;;
     esac
 done