* [platform] Add Support For Environment Variable
This PR adds the ability to read environment file from /etc/sonic.
the file contains immutable SONiC config attributes such as platform,
hwsku, version, device_type. The aim is to minimize calls being made
into sonic-cfggen during boot time.
singed-off-by: Tamer Ahmed <tamer.ahmed@microsoft.com>
* Support rw files allowlist for Sonic Secure Boot
* Improve the performance
* fix bug
* Move the config description into a md file
* Change to use a simple way to remove the blank line
* Support chmod a-x in rw folder
* Change function name
* Change some unnecessary words