Change /dev/mmcblk0 to /dev/mmcblk2. Motivation: Fix ondev SD->eMMC installation. Related: https://gitlab.com/postmarketOS/postmarketos-ondev/-/issues/61
Change /dev/mmcblk0 to /dev/mmcblk2. Motivation: Fix ondev SD->eMMC installation. Related: https://gitlab.com/postmarketOS/postmarketos-ondev/-/issues/61