Use sel4runtime for TLS management.

sel4runtime will initilise the TLS for the first thread in the process
(this should not be overridden as it was in entry.c).

Instead of using the nasty trick of de-initialising the TLS with a null
pointer to set variables in remote TLS, we use the tools from
sel4runtime that aren't so destructive to configure the state for libbmk
and to also ensure that the IPC buffer pointer is set on each thread.

The existing tooling for creating and allocating TLS can still be used
as sel4runtime makes no assumptions or changes to the size or layout of
TLS.

THe platform-independant interface for configuring the TLS from
sel4runtime is also used rather than specific implementations for
different architectures.

Fix build errors

Update copyright year to 2018 for new/significantly updated files

Split old TLS code into arch specific code

Use new simple I/O port interface

Use an ltimer backed by RPC instead of HW timer

Such that we can run multiple rump apps.

seL4: fix compilation error

seL4: Use pin instead of vector for irq lookup

seL4: Use new sel4platsupport timer API

seL4: run astyle over project

seL4: Rename arch.c interface functions

seL4: Reduce error output boilerplate

seL4: Change to use simple implementation

seL4: Add better timer and device untyped handling

seL4: Add seL4 as a target rumprun platform