item_updater_helper: implement factoryReset

helper::factoryReset in the mmc item_updater_helper needs to set the
environment variable rwreset to true so that upon reboot, the mmc
initrd scripts can perform a factory reset by recreating all r/w
volumes.

Tested: Use busctl to call the Reset method. Verify with fw_printenv
that rwreset is set to true.

Signed-off-by: Isaac Kurth <isaac.kurth@ibm.com>
Change-Id: Iea8aa5c359e5f332105b915f58aef7472eae260b
1 file changed