dracut_NM_iSCSI_ibft_table: assert the address is permanent with iBFT
The iBFT contains an address that has been gotten from DHCP, but no further details. We don't know how was it obtained, and for how long is it supposed to be valid etc. Because of this, it's not possible to for nm-initrd-generator to pass it along to NetworkManager to treat it as DHCP lease.
To be on a safe side, nm-initrd-generator treats it as a permanent address instead. Given this address is likely required for accessing a network volume that's critical for operation of a network-booted system, this is probably a wise idea.
However, when DHCP is run on the iBFT connection, it's likely to assign the very same address. Prior to NetworkManager 1.36, when the same address is assigned manually as well as dynamically, its lifetime would sometimes be that of the DHCP lease and sometimes permanent depending on various factors.
With NetworkManager/next branch merge, the precedence is clear -- the manually assigned address allways wins. Let's adjust the iBFT test to reflect that.