Added Reboot Reason for S6000 in platform 2.0
Fixed issue in process-reboot-cause
Added package uninstall code in platform de-init code for z9100, s6100
- How I did it
-> Added support for S6000 Reboot Reason
-> Added platform.py for all platforms
-> Verified show reboot-cause command with the code changes. Added UT logs with show reboot-cause
-> Modified process-reboot-cause service to start after pmon.service. In S6000, we have to wait for nvram to be loaded.
-> If reboot-cause service starts before pmon.service, show reboot-cause is showing incorrect reason.
-> Bug fix in process-reboot-cause file
- import sonic_platform
+ import sonic_platform.platform
