__init__: add new keyword

Is IPMC Accessible

Signed-off-by: Heiko Thiery <heiko.thiery@kontron.com>
Add new keyword "Set Target Address"

Signed-off-by: Heiko Thiery <heiko.thiery@kontron.com>
Use entity key for handling with hotswap sdr.

Additionaly move hotswap sdr code to picmg module.

Signed-off-by: Heiko Thiery <heiko.thiery@kontron.com>