1. Machine with multi extruder should set length of extruder offset
to extruder num
2. Register retract_restart_extra
jira:NONE
Signed-off-by: xun.zhang <xun.zhang@bambulab.com>
Change-Id: Ic3eb324cb91dc70b091c8922936d2709c361cc38
(cherry picked from commit 13df1ee7bab2bf13c9f5ffca6ad1228ff48e885e)