Expected memmap format

The memmap expected by xen-transplant is as follows:

<file offset> <memory offset> <continuous memory chunk size>

Where file offset refers to where the memory chunk is located in the vmcore file, memory offset refers to where it will be loaded into the VM's memory space.

The memory map expected by dmamonitor is very similar, except the <file offset> field is ignored:

<placeholder> <memory offset> <continuous memory chunk size>

Using this memory map dmamonitor will save the specified memory regions during snapshotting.