Move shell functions used for sysupgrade into /lib/upgrade/fit.sh.
Introduce improved fitblk boot device detection function which
works also in case ubiblock devices have not yet been created or
even UBI itself not yet being attached.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Add minimalistic tool to allow releasing /dev/fit* devices which is
needed on sysupgrade when using the fitblk driver.
The package is hidden in menuconfig, it should only be selected by
adding it to the default package selection of boards using it.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
