fw_printenv: fw_printenv must fail if asked for an unset variable
requested to merge github/fork/liuming50/fw_printenv-must-fail-if-asked-for-an-unset-variable into master
Created by: liuming50
The return status from fw_printenv must indicate failure if asked to print a variable that is unset.
Signed-off-by: Mathias Thore mathias.thore@atlascopco.com