libsel4simple-default: Issue IO port capabilities

This reflects a change in the kernel where the root task is provided an I/O Port
control capability that can be used to issue I/O ports, instead of an initial
I/O port.

New I/O port interface in simple

This changes the simple interface for getting I/O port capabilities to instead of returning
a potentially pre-existing capability for an I/O port, the caller provides a location in
a cnode to place the requested I/O port. The reason for this change is that I/O ports will
soon be being provided from the kernel by a control cap and this design keeps simple as an
information interface that does not need to do internal allocation. Rather allocation is
only performed explicitly by the caller.

Fix all the whitespace

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

Fix licenses

libsel4simple: add ioapic function to arch-simple

sel4simple: add arch specific interface

This commit defines arch_simple_t, which adds arch
specific functions to libsel4simple and its implementors,
as the seL4 API no longer allows simple implementation to be
architecture agnostic, specifically for the interrupt handling
interface.

This commit adds the x86 arch interface which defines functions
for getting irqs, msis and ioports, and the arm interface
which just defines irqs.

libsel4simple-stable has been updated to implement the new
interface and users should not be effected. However, other
implementations of simple will need to be updated.

libsel4platsupport has been updated such that the hpet driver
wrapper now works with the lastest seL4 kernel.