Cleanup slave parameters

Cleanup slave parameters

This is the first step towards having alignment of the job structure, applying
commit gating and use of labels for all installer jobs.

Apart from the above, it also
- puts all CI baremetal and virtual PODs together
- gets rid of use of slaves directly for CI baremetal and virtual PODs
- switches labels for all CI baremetal and virtual PODs using below labels
    {installer}-baremetal
    {installer}-virtual
- puts all CI build slaves together and switches to labels - except huawei-build
- puts all none-CI PODs together

Please note that this change does not impact the overall job structure.

Change-Id: I2d8d15799a57fe7e063d39f81b96d19c218b100e
Signed-off-by: Fatih Degirmenci <fatih.degirmenci@ericsson.com>