Remove outdated try except block in ec2 code

We now have 'ec2_id -> glance_id mapping' so this check can be removed

Change-Id: Ib10ab5faea154bae9d129c0dc1edc24c2a99ffb7
Merge "Remove outdated try except block in ec2 code"
Merge remote-tracking branch 'm_src_repo/master' into build-temp