libplatsupport: use const qualifiers

Signed-off-by: Axel Heider <axelheider@gmx.de>

trivial: code formatting

Improve readability, add comments, apply coding style

Signed-off-by: Axel Heider <axelheider@gmx.de>

trivial: Style changed files

libplatsupport: Add interface registration iface

This commit adds in a new interface for the registration of other
interfaces. More specifically, driver or service interfaces. This new
interface is only a skeleton interface and is intended to be implemented
by other libraries.

libplatsupport: Add IRQ ops to IO ops structure

The IO ops structure should contain all interfaces necessary for drivers
to function, this includes the registration of IRQs. Hence we add the
IRQ ops structure to the IO ops structure.

libplatsupport: Abstract the FDT interface

This commit modifies the FDT interface to let it hide behind an
abstraction layer. This is intended to allow the underlying
implementations to hide its implementation details.

platsupport: added ps_io_fdt in interface

Change was in ps_io_ops to point dtb blob

platsupport: add stdlib malloc ops impl

This is migrated from sel4platsupport, as it is not sel4 dependant

pragma once and for all

trivial: Pass a reference to a ptr in ps_malloc etc

platsupport: add ps_malloc_ops to io.h

Provides alloc/calloc/free for drivers.

Fix whitespace

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

fix licenses

Use CONFIG_ variables instead of configuration definitions

libplatsupport: add inlines for device register bitfield manipulation