Fixes generating of toci_env

if toci_functions.sh file is sourced then "-e 'CLOUD_ADMIN_PASSWORD'"
expression matches the "declare | ..." line in get_tocienv function.
Then this line is written into toci_env too, which causes that if
toci_env file is sourced it's emptied.

Change-Id: I91a748e762f769975e79f35c89e390270722afa1