sel4vspace: Deferred rights reservation mapping

This extends the sel4vspace interface to support the ability to
create reservations where the rights for the memory region are
deferred to the vspace mapping invocation. This is useful when the
creation of a reservation and the mapping of the reservation are
not local and the rights cannot be determined during reservation
creation.

seL4_libs: remove autoconf.h from seL4_libs

this commit removes autoconf.h generation from each lib and
append '#include <<lib_name>/gen_config.h>' after each
'#include <autoconf.h>' since autoconf.h is only the for the
kernel config now. This is a temporarily solution, since we
currently don't have a way to tell which header files each file
is trying to include when it includes 'autoconf.h'

sel4vspace: Style include/vspace/vspace.h

Ran style over file 'libsel4vspace/include/vspace/vspace.h'.

sel4vspace: Enable sharing of mem range 0x0-0x1000

Removed to check on start addr being NULL as the user may want to
map the address range including 0x0 - 0x1000.

sel4vspace: Page access with callback function

Implemented a 'vspace_access_page_with_callback' function. This
performs a mapping of a page from a source to destination vspace.
The mapping is subsequently passed to a user defined callback
before being unmapped out of the destination vspace.

pragma once and for all

SELFOUR-1053: Invoke VMM layer directly in vpsace_[new/map]_pages()

This change brings the behaviour of vspace_[new/map]_pages() in line with its
expected behaviour as the OS page-level combinatorial allocator -- such an
allocator is expected to directly call on the PMM and VMM for frames and pages
respectively, then map the frames into the pages, and do some book-keeping
before handing out the new vmem to userspace.

The previous implementation of vspace_[new/map]_pages had a call to
vspace_new_reservation which in turn had a call to malloc somewhere internally,
and this was causing a circular call path in our libraries.

Fix all the whitespace

- remove trailing whitespace
- remove duplicate blank lines
- remove blank lines at end of files

vspace_new_pages: New configuration behavior

Fix licenses

SELFOUR-567: use seL4_CapRights_t

sel4vspace: Fix typo in comment

sel4[utils|vspace] handle 0 sized stacks

sel4vspace: allow custom stack size

This allows a user to provide a custom
stack size via the new function vspace_new_sized_stack
and companion free function.

The previous vspace_new_stack is maintained to avoid
breaking the API.

libsel4vspace: add missing return statements

libsel4vspace: Add check

libsel4vspace: Remove 32-bit assumptions in printing

libsel4vspace: Make cookies pointer sized, not 32-bit

libsel4utils: Import page.h definitions from libutils

The page sizes supported by a system are a combination of both the
raw architecture, as well as how seL4 is configured. This makes these
definitions system specific, hence the need to move them

As a consequence of having these defined in libsel4utils it is no
longer possible for libsel4vspace to use them, as libsel4utils
already depends upon libsel4vspace, and we do not support dual
dependencies in the build system. To compensate these checks are
added to the vspace implementation in libsel4utils