common: add support to sign boot image

adding rules for generating signed boot image

Change-Id: I53710c2b4b8e8750c29d9c46c51a3e4ff0f270d2
Merge "common: add support to sign boot image"
common: init: Change permission for bypass_vchg_loop_debouncer

Change owner and permission for bypass_vchg_loop_debouncer to make sure
charger_monitor can do write access to this entry.

Change-Id: I25809991bb12e763fc1233acb9a34b818f24e815
Merge "common: init: Change permission for bypass_vchg_loop_debouncer"