boot/grub: add rootwait to default config
It doesn't hurt, and is useful for removable boot media like a pendrive
that may depend on usb enumeration and isn't available immediately.
Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Gustavo Zacarias