ANDROID: arm64/mm: implement {populate/depopulate}_range_driver_managed

After certain memory blocks are offlined, some usecases require that the
page-table mappings are removed while still keeping the memblock device nodes,
memory resources and the memmap entries intact. This is to avoid the overhead
involved in using 'remove_memory' if the offlined blocks will be added/onlined
back into the system at later point. {populate/depopulate}_range_driver_managed
provide the abilty to drivers to tear-down and create page-table mappings of
memory blocks that its managing, without having to use 'remove_memory' and
friends for the purpose.
These functions does not interfere with mappings of boot memory or resources
that isn't owned by the driver.

Bug: 171907330
Change-Id: Ie11201334bd7438bf87f933ccc81814fa99162c4
Signed-off-by: Sudarshan Rajagopalan <sudaraja@codeaurora.org>