Fix the curl command in the ironic-deploy element

We need to use the eval command together with curl so that the
$TOKEN_HEADER variable is seems by curl as two arguments: "-H" and
"'X-Auth-Token: ...". Without the eval bash would interpret the variable
as only one argument "-H 'X-Auth-Token: ...'" making the curl command
to not understand that parameter and fail to pass the auth_token to the
Ironic API.

Change-Id: I4dcfc323d6ab9b7fa207328386ef65a146a93617
Merge "Fix the curl command in the ironic-deploy element"