system: fix unmet dependencies

Don't force remounting / read/write when using a customskeleton and
systemd as init system, to fix the following unmet dependencies:

    warning: (BR2_INIT_SYSTEMD) selects BR2_TARGET_GENERIC_REMOUNT_ROOTFS_RW
    which has unmet direct dependencies (BR2_ROOTFS_SKELETON_DEFAULT)

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
1 file changed