NTB: MFV ab760a0c: Add split BAR support for Haswell

On the Haswell platform, a split BAR option to allow creation of 2 32bit
BARs (4 and 5) from the 64bit BAR 4. Adding support for this new option.

Authored by: Dave Jiang
Obtained from: Linux (Dual BSD/GPL driver)
Sponsored by: EMC / Isilon Storage Division