[build] Make .liso image generation silent unless errors occur

diff --git a/src/util/genliso b/src/util/genliso
index 1782384..ac9924a 100755 (executable)
--- a/src/util/genliso
+++ b/src/util/genliso
@@ -70,6 +70,6 @@ then
        exit 1
 fi
 
-mkisofs -o $out -c boot.cat -b boot.img $dir
+mkisofs -q -o $out -c boot.cat -b boot.img $dir
 
 rm -fr $dir