VMUserAddressSpace: Use std::min/max instead of min/max_c
VMUserAddressSpace: Small coding style fixes
VMUserAddressSpace::_InsertAreaSlot(): Fix base address handling

Unless a free range was found before the first area a specified base
address was ignored. In the non-randomized case this could result in
a range other than (i.e. starting before) the preferred one being
chosen, although the preferred range was available.
VMUserAddressSpace: Use align_address() instead of ROUNDUP()

Mainly for aesthetical reasons.
mmap(): Fix !MAP_FIXED with non-NULL address case

In that case the caller ideally wants to obtain an allocation at the
specified address, which was thwarted by using
B_RANDOMIZED_BASE_ADDRESS. Use B_BASE_ADDRESS instead.

This improves the experience with the gcc 4 pre-compiled headers
implementation (which expects to be able to map the PCH file at the same
address where it was located originally when it had been created), but
doesn't fix it completely. As long as ASLR is active, it is always
possible that something else (mapped shared objects, heap, stack) is in
the way.
Add the webpositive hpkg to the repository haiku.

e.g., jam -q @release-raw build \<repository\>haiku