scripts/archive-source: silence subprojects downloads

It's too verbose.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-ID: <20250924120426.2158655-5-marcandre.lureau@redhat.com>

scripts/archive-source.sh

@@ -77,7 +77,7 @@ function subproject_dir() {
 git archive --format tar "$(tree_ish)" > "$tar_file"
 test $? -ne 0 && error "failed to archive qemu"
 
-meson subprojects download $subprojects
+meson subprojects download $subprojects >/dev/null
 test $? -ne 0 && error "failed to download subprojects $subprojects"
 
 for sp in $subprojects; do